diff --git a/src/messenger/tests/server_side/webim/libs/classes/ThreadTest.php b/src/messenger/tests/server_side/webim/libs/classes/ThreadTest.php
index 08f59f56..9cab8d5e 100644
--- a/src/messenger/tests/server_side/webim/libs/classes/ThreadTest.php
+++ b/src/messenger/tests/server_side/webim/libs/classes/ThreadTest.php
@@ -202,6 +202,7 @@ class ThreadTest extends PHPUnit_Framework_TestCase {
 
 			'lrevision' => 189,
 			'istate' => Thread::STATE_QUEUE,
+			'invitationstate' => Thread::INVITATION_NOT_INVITED,
 			'ltoken' => 19908,
 
 			'nextagent' => 0,
@@ -574,15 +575,19 @@ class ThreadTest extends PHPUnit_Framework_TestCase {
 			'agentId' => 12,
 			'tmessage' => 'New message text',
 			'dtmcreated' => time(),
-			'tname' => 'Sender name'
+			'tname' => 'Sender name',
+			'plugin' => '',
+			'data' => array()
 		);
 
 		$message['messageid'] = $thread->postMessage(
 			$message['ikind'],
 			$message['tmessage'],
-			$message['tname'],
-			$message['agentId'],
-			$message['dtmcreated']
+			array(
+				'name' => $message['tname'],
+				'operator_id' => $message['agentId'],
+				'created' => $message['dtmcreated']
+			)
 		);
 		// Load message info from database
 		$msg_info = $db->query(
@@ -590,6 +595,8 @@ class ThreadTest extends PHPUnit_Framework_TestCase {
 			array($message['messageid']),
 			array('return_rows' => Database::RETURN_ONE_ROW)
 		);
+		$msg_info['data'] = unserialize($msg_info['data']);
+
 		// Check values
 		$this->assertEquals($message, $msg_info);
 
@@ -613,21 +620,27 @@ class ThreadTest extends PHPUnit_Framework_TestCase {
 			'kind' => Thread::KIND_USER,
 			'message' => 'The first message',
 			'created' => time(),
-			'name' => 'System message only for agent'
+			'name' => 'System message only for agent',
+			'plugin' => 'f_test_plg',
+			'data' => array('msg_num' => 1)
 		);
 		// The second
 		$second_message = array(
 			'kind' => Thread::KIND_AGENT,
 			'message' => 'The second message',
 			'created' => time(),
-			'name' => 'User'
+			'name' => 'User',
+			'plugin' => 'f_test_plg',
+			'data' => array('msg_num' => 1)
 		);
 		// The third
 		$third_message = array(
 			'kind' => Thread::KIND_FOR_AGENT,
 			'message' => 'The third message',
 			'created' => time(),
-			'name' => 'Agent'
+			'name' => 'Agent',
+			'plugin' => 'f_test_plg',
+			'data' => array('msg_num' => 1)
 		);
 
 		// Send messages
@@ -635,25 +648,37 @@ class ThreadTest extends PHPUnit_Framework_TestCase {
 		$first_message['id'] = $thread->postMessage(
 			$first_message['kind'],
 			$first_message['message'],
-			$first_message['name'],
-			12,
-			$first_message['created']
+			array(
+				'name' => $first_message['name'],
+				'operator_id' => 12,
+				'created' => $first_message['created'],
+				'plugin' => $second_message['plugin'],
+				'data' => $second_message['data']
+			)
 		);
 		// The second
 		$second_message['id'] = $thread->postMessage(
 			$second_message['kind'],
 			$second_message['message'],
-			$second_message['name'],
-			14,
-			$second_message['created']
+			array(
+				'name' => $second_message['name'],
+				'operator_id' => 14,
+				'created' => $second_message['created'],
+				'plugin' => $second_message['plugin'],
+				'data' => $second_message['data']
+			)
 		);
 		// The third
 		$third_message['id'] = $thread->postMessage(
 			$third_message['kind'],
 			$third_message['message'],
-			$third_message['name'],
-			16,
-			$third_message['created']
+			array(
+				'name' => $third_message['name'],
+				'operator_id' => 16,
+				'created' => $third_message['created'],
+				'plugin' => $second_message['plugin'],
+				'data' => $second_message['data']
+			)
 		);
 
 		// Check messages for agent with ids starts from $msg_id
diff --git a/src/messenger/webim/install/dbinfo.php b/src/messenger/webim/install/dbinfo.php
index be0d1f22..df15d2b9 100644
--- a/src/messenger/webim/install/dbinfo.php
+++ b/src/messenger/webim/install/dbinfo.php
@@ -127,6 +127,11 @@ $dbtables = array(
 		"agentId" => "int NOT NULL DEFAULT 0",
 		// Message text body.
 		"tmessage" => "text NOT NULL",
+		// Name of the plugin which sent the message. If message was not sent by
+		// a plugin this field equals to an empty string.
+		"plugin" => "varchar(256) NOT NULL DEFAULT ''",
+		// Arbitrary serialized data related with message.
+		"data" => "text",
 		// Unix timestamp when message was created.
 		"dtmcreated" => "int NOT NULL DEFAULT 0",
 		// Name of the message sender.
@@ -266,7 +271,7 @@ $dbtables_can_update = array(
 	"${mysqlprefix}chatthread" => array("agentId", "userTyping", "agentTyping", "messageCount", "nextagent", "shownmessageid", "userid", "userAgent", "groupid", "dtmchatstarted", "invitationstate"),
 	"${mysqlprefix}chatthreadstatistics" => array("missedthreads", "sentinvitations", "acceptedinvitations", "rejectedinvitations", "ignoredinvitations"),
 	"${mysqlprefix}requestbuffer" => array("requestid", "requestkey", "request"),
-	"${mysqlprefix}chatmessage" => array("agentId"),
+	"${mysqlprefix}chatmessage" => array("agentId", "plugin", "data"),
 	"${mysqlprefix}chatoperator" => array("vcavatar", "vcjabbername", "iperm", "istatus", "idisabled", "vcemail", "dtmrestore", "vcrestoretoken", "code"),
 	"${mysqlprefix}chatoperatorstatistics" => array("sentinvitations", "acceptedinvitations", "rejectedinvitations", "ignoredinvitations"),
 	"${mysqlprefix}chatban" => array(),
diff --git a/src/messenger/webim/install/dbperform.php b/src/messenger/webim/install/dbperform.php
index 5aa1e8d8..9262ecb4 100644
--- a/src/messenger/webim/install/dbperform.php
+++ b/src/messenger/webim/install/dbperform.php
@@ -91,6 +91,14 @@ if ($act == "silentcreateall") {
 			runsql("update ${mysqlprefix}chatmessage, ${mysqlprefix}chatoperator set agentId = operatorid where agentId = 0 AND ikind = 2 AND (vclocalename = tname OR vccommonname = tname)", $link);
 		}
 
+		if (in_array("${mysqlprefix}chatmessage.plugin", $absent_columns)) {
+			runsql("ALTER TABLE ${mysqlprefix}chatmessage ADD plugin varchar(256) NOT NULL DEFAULT '' AFTER tmessage", $link);
+		}
+
+		if (in_array("${mysqlprefix}chatmessage.data", $absent_columns)) {
+			runsql("ALTER TABLE ${mysqlprefix}chatmessage ADD data text AFTER plugin", $link);
+		}
+
 		if (in_array("${mysqlprefix}chatthread.agentId", $absent_columns)) {
 			runsql("ALTER TABLE ${mysqlprefix}chatthread ADD agentId int NOT NULL DEFAULT 0 AFTER agentName", $link);
 			runsql("update ${mysqlprefix}chatthread, ${mysqlprefix}chatoperator set agentId = operatorid where agentId = 0 AND (vclocalename = agentName OR vccommonname = agentName)", $link);
diff --git a/src/messenger/webim/js/compiled/chat/collections/messages.js b/src/messenger/webim/js/compiled/chat/collections/messages.js
index 5c2e87c7..cc94e1bd 100644
--- a/src/messenger/webim/js/compiled/chat/collections/messages.js
+++ b/src/messenger/webim/js/compiled/chat/collections/messages.js
@@ -6,5 +6,5 @@
      http://www.apache.org/licenses/LICENSE-2.0
 */
 (function(b,d,j){b.Collections.Messages=d.Collection.extend({model:b.Models.Message,initialize:function(){this.periodicallyCalled=[];this.periodicallyCalled.push(b.Objects.server.callFunctionsPeriodically(j.bind(this.updateMessagesFunctionBuilder,this),j.bind(this.updateMessages,this)))},finalize:function(){for(var a=0;a<this.periodicallyCalled.length;a++)b.Objects.server.stopCallFunctionsPeriodically(this.periodicallyCalled[a])},updateMessages:function(a){a.lastId&&b.Objects.Models.thread.set({lastId:a.lastId});
-for(var k=b.Models.Message.prototype.KIND_PLUGIN,g=[],c,f,e,h=0,d=a.messages.length;h<d;h++)c=a.messages[h],c.kind!=k?g.push(new b.Models.Message(c)):"object"!=typeof c.message||null===c.message||(f=c.message.plugin||!1,f="process:"+(!1!==f?f+":":"")+"plugin:message",e={messageData:c,model:!1},this.trigger(f,e),e.model&&(e.model.get("id")||e.model.set({id:c.id}),g.push(e.model)));0<g.length&&this.add(g)},updateMessagesFunctionBuilder:function(){var a=b.Objects.Models.thread,d=b.Objects.Models.user;
-return[{"function":"updateMessages",arguments:{"return":{messages:"messages",lastId:"lastId"},references:{},threadId:a.get("id"),token:a.get("token"),lastId:a.get("lastId"),user:!d.get("isAgent")}}]},add:function(){var a=Array.prototype.slice.apply(arguments),a=d.Collection.prototype.add.apply(this,a);this.trigger("multiple:add");return a}})})(Mibew,Backbone,_);
+for(var k=b.Models.Message.prototype.KIND_PLUGIN,g=[],c,f,e,h=0,d=a.messages.length;h<d;h++)c=a.messages[h],c.kind!=k?g.push(new b.Models.Message(c)):"object"!=typeof c.data||null===c.data||(f=c.plugin||!1,f="process:"+(!1!==f?f+":":"")+"plugin:message",e={messageData:c,model:!1},this.trigger(f,e),e.model&&(e.model.get("id")||e.model.set({id:c.id}),g.push(e.model)));0<g.length&&this.add(g)},updateMessagesFunctionBuilder:function(){var a=b.Objects.Models.thread,d=b.Objects.Models.user;return[{"function":"updateMessages",
+arguments:{"return":{messages:"messages",lastId:"lastId"},references:{},threadId:a.get("id"),token:a.get("token"),lastId:a.get("lastId"),user:!d.get("isAgent")}}]},add:function(){var a=Array.prototype.slice.apply(arguments),a=d.Collection.prototype.add.apply(this,a);this.trigger("multiple:add");return a}})})(Mibew,Backbone,_);
diff --git a/src/messenger/webim/js/compiled/chat_app.js b/src/messenger/webim/js/compiled/chat_app.js
index 90fccc31..a2dc6592 100644
--- a/src/messenger/webim/js/compiled/chat_app.js
+++ b/src/messenger/webim/js/compiled/chat_app.js
@@ -157,8 +157,8 @@ groupId:a.get("groupId"),name:a.get("name"),info:a.get("info"),email:a.get("emai
      http://www.apache.org/licenses/LICENSE-2.0
 */
 (function(b,d,j){b.Collections.Messages=d.Collection.extend({model:b.Models.Message,initialize:function(){this.periodicallyCalled=[];this.periodicallyCalled.push(b.Objects.server.callFunctionsPeriodically(j.bind(this.updateMessagesFunctionBuilder,this),j.bind(this.updateMessages,this)))},finalize:function(){for(var a=0;a<this.periodicallyCalled.length;a++)b.Objects.server.stopCallFunctionsPeriodically(this.periodicallyCalled[a])},updateMessages:function(a){a.lastId&&b.Objects.Models.thread.set({lastId:a.lastId});
-for(var k=b.Models.Message.prototype.KIND_PLUGIN,g=[],c,f,e,h=0,d=a.messages.length;h<d;h++)c=a.messages[h],c.kind!=k?g.push(new b.Models.Message(c)):"object"!=typeof c.message||null===c.message||(f=c.message.plugin||!1,f="process:"+(!1!==f?f+":":"")+"plugin:message",e={messageData:c,model:!1},this.trigger(f,e),e.model&&(e.model.get("id")||e.model.set({id:c.id}),g.push(e.model)));0<g.length&&this.add(g)},updateMessagesFunctionBuilder:function(){var a=b.Objects.Models.thread,d=b.Objects.Models.user;
-return[{"function":"updateMessages",arguments:{"return":{messages:"messages",lastId:"lastId"},references:{},threadId:a.get("id"),token:a.get("token"),lastId:a.get("lastId"),user:!d.get("isAgent")}}]},add:function(){var a=Array.prototype.slice.apply(arguments),a=d.Collection.prototype.add.apply(this,a);this.trigger("multiple:add");return a}})})(Mibew,Backbone,_);
+for(var k=b.Models.Message.prototype.KIND_PLUGIN,g=[],c,f,e,h=0,d=a.messages.length;h<d;h++)c=a.messages[h],c.kind!=k?g.push(new b.Models.Message(c)):"object"!=typeof c.data||null===c.data||(f=c.plugin||!1,f="process:"+(!1!==f?f+":":"")+"plugin:message",e={messageData:c,model:!1},this.trigger(f,e),e.model&&(e.model.get("id")||e.model.set({id:c.id}),g.push(e.model)));0<g.length&&this.add(g)},updateMessagesFunctionBuilder:function(){var a=b.Objects.Models.thread,d=b.Objects.Models.user;return[{"function":"updateMessages",
+arguments:{"return":{messages:"messages",lastId:"lastId"},references:{},threadId:a.get("id"),token:a.get("token"),lastId:a.get("lastId"),user:!d.get("isAgent")}}]},add:function(){var a=Array.prototype.slice.apply(arguments),a=d.Collection.prototype.add.apply(this,a);this.trigger("multiple:add");return a}})})(Mibew,Backbone,_);
 /*
  Copyright 2005-2013 the original author or authors.
  Licensed under the Apache License, Version 2.0 (the "License").
diff --git a/src/messenger/webim/js/compiled/default/models/message.js b/src/messenger/webim/js/compiled/default/models/message.js
index 196e5d5b..8438f7fa 100644
--- a/src/messenger/webim/js/compiled/default/models/message.js
+++ b/src/messenger/webim/js/compiled/default/models/message.js
@@ -5,4 +5,4 @@
  You may obtain a copy of the License at
      http://www.apache.org/licenses/LICENSE-2.0
 */
-(function(a){a.Models.Message=a.Models.Base.extend({defaults:{kind:null,created:0,name:"",message:""},KIND_USER:1,KIND_AGENT:2,KIND_FOR_AGENT:3,KIND_INFO:4,KIND_CONN:5,KIND_EVENTS:6,KIND_PLUGIN:7})})(Mibew);
+(function(a){a.Models.Message=a.Models.Base.extend({defaults:{kind:null,created:0,name:"",message:"",plugin:"",data:{}},KIND_USER:1,KIND_AGENT:2,KIND_FOR_AGENT:3,KIND_INFO:4,KIND_CONN:5,KIND_EVENTS:6,KIND_PLUGIN:7})})(Mibew);
diff --git a/src/messenger/webim/js/compiled/default_app.js b/src/messenger/webim/js/compiled/default_app.js
index 16403405..1f7cf1f2 100644
--- a/src/messenger/webim/js/compiled/default_app.js
+++ b/src/messenger/webim/js/compiled/default_app.js
@@ -73,7 +73,7 @@ b.Utils.playSound=function(a){c("body").append('<audio autoplay style="display:
  You may obtain a copy of the License at
      http://www.apache.org/licenses/LICENSE-2.0
 */
-(function(a){a.Models.Message=a.Models.Base.extend({defaults:{kind:null,created:0,name:"",message:""},KIND_USER:1,KIND_AGENT:2,KIND_FOR_AGENT:3,KIND_INFO:4,KIND_CONN:5,KIND_EVENTS:6,KIND_PLUGIN:7})})(Mibew);
+(function(a){a.Models.Message=a.Models.Base.extend({defaults:{kind:null,created:0,name:"",message:"",plugin:"",data:{}},KIND_USER:1,KIND_AGENT:2,KIND_FOR_AGENT:3,KIND_INFO:4,KIND_CONN:5,KIND_EVENTS:6,KIND_PLUGIN:7})})(Mibew);
 /*
  Copyright 2005-2013 the original author or authors.
  Licensed under the Apache License, Version 2.0 (the "License").
diff --git a/src/messenger/webim/js/compiled/thread_log/app.js b/src/messenger/webim/js/compiled/thread_log/app.js
index 0c4c477b..06852c5b 100644
--- a/src/messenger/webim/js/compiled/thread_log/app.js
+++ b/src/messenger/webim/js/compiled/thread_log/app.js
@@ -5,4 +5,4 @@
  You may obtain a copy of the License at
      http://www.apache.org/licenses/LICENSE-2.0
 */
-(function(b,c){var a=new c.Marionette.Application;a.addRegions({messagesRegion:"#messages-region"});a.addInitializer(function(c){a.messagesRegion.show(new b.Views.MessagesCollection({collection:new b.Collections.Messages(c.messages)}))});b.Application=a})(Mibew,Backbone);
+(function(a,c){var b=new c.Marionette.Application;b.addRegions({messagesRegion:"#messages-region"});b.addInitializer(function(c){var d=new a.Collections.Messages;a.Objects.Collections.messages=d;d.updateMessages(c.messages);b.messagesRegion.show(new a.Views.MessagesCollection({collection:d}))});a.Application=b})(Mibew,Backbone);
diff --git a/src/messenger/webim/js/compiled/thread_log/collections/messages.js b/src/messenger/webim/js/compiled/thread_log/collections/messages.js
index 39cbdf1c..1186348d 100644
--- a/src/messenger/webim/js/compiled/thread_log/collections/messages.js
+++ b/src/messenger/webim/js/compiled/thread_log/collections/messages.js
@@ -5,4 +5,4 @@
  You may obtain a copy of the License at
      http://www.apache.org/licenses/LICENSE-2.0
 */
-(function(a,b){a.Collections.Messages=b.Collection.extend({model:a.Models.Message})})(Mibew,Backbone,_);
+(function(d,e){d.Collections.Messages=e.Collection.extend({model:d.Models.Message,updateMessages:function(b){for(var c=[],a=0;a<b.length;a++)b[a].message&&c.push(b[a]);0<c.length&&this.add(c)}})})(Mibew,Backbone,_);
diff --git a/src/messenger/webim/js/compiled/thread_log_app.js b/src/messenger/webim/js/compiled/thread_log_app.js
index 7174db94..7cd532ba 100644
--- a/src/messenger/webim/js/compiled/thread_log_app.js
+++ b/src/messenger/webim/js/compiled/thread_log_app.js
@@ -4,7 +4,7 @@
  You may obtain a copy of the License at
      http://www.apache.org/licenses/LICENSE-2.0
 */
-(function(a,b){a.Collections.Messages=b.Collection.extend({model:a.Models.Message})})(Mibew,Backbone,_);
+(function(d,e){d.Collections.Messages=e.Collection.extend({model:d.Models.Message,updateMessages:function(b){for(var c=[],a=0;a<b.length;a++)b[a].message&&c.push(b[a]);0<c.length&&this.add(c)}})})(Mibew,Backbone,_);
 /*
  Copyright 2005-2013 the original author or authors.
  Licensed under the Apache License, Version 2.0 (the "License").
@@ -18,4 +18,4 @@
  You may obtain a copy of the License at
      http://www.apache.org/licenses/LICENSE-2.0
 */
-(function(b,c){var a=new c.Marionette.Application;a.addRegions({messagesRegion:"#messages-region"});a.addInitializer(function(c){a.messagesRegion.show(new b.Views.MessagesCollection({collection:new b.Collections.Messages(c.messages)}))});b.Application=a})(Mibew,Backbone);
+(function(a,c){var b=new c.Marionette.Application;b.addRegions({messagesRegion:"#messages-region"});b.addInitializer(function(c){var d=new a.Collections.Messages;a.Objects.Collections.messages=d;d.updateMessages(c.messages);b.messagesRegion.show(new a.Views.MessagesCollection({collection:d}))});a.Application=b})(Mibew,Backbone);
diff --git a/src/messenger/webim/js/source/chat/collections/messages.js b/src/messenger/webim/js/source/chat/collections/messages.js
index e7d2d9c6..1be4bee2 100644
--- a/src/messenger/webim/js/source/chat/collections/messages.js
+++ b/src/messenger/webim/js/source/chat/collections/messages.js
@@ -81,15 +81,10 @@
 
                     // Message have KIND_PLUGIN kind and need to be processed
                     // by plugins to know how to display it.
-                    //
-                    // Message treat as data object with following fields:
-                    //  - 'plugin': string, name of the plugin which sent the
-                    //    message;
-                    //  - 'data': object, some data sent by the plugin.
 
                     // Check if message is an real Object
-                    if ((typeof messageData.message != 'object')
-                        || (messageData.message === null)) {
+                    if ((typeof messageData.data != 'object')
+                        || (messageData.data === null)) {
                         continue;
                     }
 
@@ -98,7 +93,7 @@
                     // If plugin name was specified it will be
                     // 'process:<plugin_name>:plugin:message' and
                     // 'process:plugin:message' otherwise.
-                    pluginName = messageData.message.plugin || false;
+                    pluginName = messageData.plugin || false;
                     eventName = 'process:'
                         + ((pluginName !== false) ? pluginName + ':' : '')
                         + 'plugin:message';
diff --git a/src/messenger/webim/js/source/default/models/message.js b/src/messenger/webim/js/source/default/models/message.js
index 259ac713..19106ecc 100644
--- a/src/messenger/webim/js/source/default/models/message.js
+++ b/src/messenger/webim/js/source/default/models/message.js
@@ -40,7 +40,20 @@
                  * Text of the message
                  * @type String
                  */
-                message: ''
+                message: '',
+
+                /**
+                 * Name of the plugin which sent the message. If message was not
+                 * sent by a plugin it equals to an empty string.
+                 * @type String
+                 */
+                plugin: '',
+
+                /**
+                 * Set of arbitrary data attached to the message.
+                 * @type Object
+                 */
+                data: {}
             },
 
             /** Message kind constants */
diff --git a/src/messenger/webim/js/source/thread_log/app.js b/src/messenger/webim/js/source/thread_log/app.js
index fae4515b..bd3f972e 100644
--- a/src/messenger/webim/js/source/thread_log/app.js
+++ b/src/messenger/webim/js/source/thread_log/app.js
@@ -18,8 +18,16 @@
 
     // Initialize application
     App.addInitializer(function(options){
+        // Create new empty messages collection and store it
+        var messages = new Mibew.Collections.Messages();
+        Mibew.Objects.Collections.messages = messages;
+
+        // Update messages in the collection
+        messages.updateMessages(options.messages);
+
+        // Dispaly collection
         App.messagesRegion.show(new Mibew.Views.MessagesCollection({
-            collection: new Mibew.Collections.Messages(options.messages)
+            collection: messages
         }));
     });
 
diff --git a/src/messenger/webim/js/source/thread_log/collections/messages.js b/src/messenger/webim/js/source/thread_log/collections/messages.js
index 9efed02c..bf5ec41f 100644
--- a/src/messenger/webim/js/source/thread_log/collections/messages.js
+++ b/src/messenger/webim/js/source/thread_log/collections/messages.js
@@ -18,7 +18,29 @@
              * Default contructor for model
              * @type Function
              */
-            model: Mibew.Models.Message
+            model: Mibew.Models.Message,
+
+            /**
+             * Update messages in collection.
+             *
+             * Skip messages with empty text body.
+             * @param rawMessages {Array} Array of row message models data.
+             */
+            updateMessages: function(rawMessages) {
+                // Reject all messages with empty text body
+                var newMessages = [];
+                for(var i = 0; i < rawMessages.length; i++) {
+                    if (! rawMessages[i].message) {
+                        continue;
+                    }
+                    newMessages.push(rawMessages[i]);
+                }
+
+                // Add new messages to the collection
+                if (newMessages.length > 0) {
+                    this.add(newMessages);
+                }
+            }
         }
     );
 
diff --git a/src/messenger/webim/libs/classes/thread.php b/src/messenger/webim/libs/classes/thread.php
index 91a5e04c..ecb300f2 100644
--- a/src/messenger/webim/libs/classes/thread.php
+++ b/src/messenger/webim/libs/classes/thread.php
@@ -563,9 +563,10 @@ Class Thread {
 					$this->postMessage(
 						self::KIND_CONN,
 						$message_to_post,
-						null,
-						null,
-						$last_ping_other_side + self::CONNECTION_TIMEOUT
+						array(
+							'created' => $last_ping_other_side
+								+ self::CONNECTION_TIMEOUT
+						)
 					);
 
 					// And update thread
@@ -582,9 +583,10 @@ Class Thread {
 				$this->postMessage(
 					self::KIND_FOR_AGENT,
 					$message_to_post,
-					null,
-					null,
-					$last_ping_other_side + self::CONNECTION_TIMEOUT
+					array(
+						'created' => $last_ping_other_side
+							+ self::CONNECTION_TIMEOUT
+					)
 				);
 			}
 		}
@@ -690,8 +692,10 @@ Class Thread {
 	 *  - 'kind': int, message kind, see Thread::KIND_* for details;
 	 *  - 'created': int, unix timestamp when message was created;
 	 *  - 'name': string, name of sender;
-	 *  - 'message': associative array with message data if kind equals to
-	 *    Thread::KIND_PLUGIN and message text string otherwise.
+	 *  - 'message': string, message text;
+	 *  - 'plugin': string, name of the plugin which sent the message or an
+	 *    empty string if message was not sent by a plugin.
+	 *  - 'data' array, arbitrary data attached to the message
 	 * @see Thread::postMessage()
 	 */
 	public function getMessages($is_user, &$last_id) {
@@ -702,7 +706,7 @@ Class Thread {
 		// Load messages
 		$messages = $db->query(
 			"select messageid as id, ikind as kind, dtmcreated as created, " .
-			" tname as name, tmessage as message " .
+			" tname as name, tmessage as message, plugin, data " .
 			"from {chatmessage} " .
 			"where threadid = :threadid and messageid > :lastid " .
 			($is_user ? "and ikind <> " . self::KIND_FOR_AGENT : "") .
@@ -722,21 +726,22 @@ Class Thread {
 				$msg['name']
 			);
 
-			// Process message body
-			if ($messages[$key]['kind'] == self::KIND_PLUGIN) {
-				// Treat plugin message body as an associative array
-				$messages[$key]['message'] = unserialize(
-					$messages[$key]['message']
+			// Process data attached to the message
+			if (! empty($messages[$key]['data'])) {
+				$messages[$key]['data'] = unserialize(
+					$messages[$key]['data']
 				);
 			} else {
-				// Change message body encoding for core messages kinds
-				$messages[$key]['message'] = myiconv(
-					$webim_encoding,
-					"utf-8",
-					$msg['message']
-				);
+				$messages[$key]['data'] = array();
 			}
 
+			// Change message body encoding
+			$messages[$key]['message'] = myiconv(
+				$webim_encoding,
+				"utf-8",
+				$msg['message']
+			);
+
 			// Get last message ID
 			if ($msg['id'] > $last_id) {
 				$last_id = $msg['id'];
@@ -749,20 +754,30 @@ Class Thread {
 	/**
 	 * Send the messsage
 	 *
-	 * Use to send message with one of the core kinds(not Thread::KIND_PLUGIN).
-	 * Trigger error with 'E_USER_WARNING' level if $kind equals to
-	 * Thread::KIND_PLUGIN.
+	 * One can attach arbitrary data to the message by setting 'data' item
+	 * in the $options array. DO NOT serialize data manually - it will be
+	 * automatically coverted to array and serialized before save in database
+	 * and unserialized after retreive form database.
 	 *
-	 * To send plugin message use Thread::postPluginMessage instead.
+	 * One can also set plugin item of the $options array to indicate that
+	 * message was sent by a plugin.
 	 *
-	 * @param int $kind Message kind. One of the Thread::KIND_* but not
-	 * Thread::KIND_PLUGIN
+	 * @param int $kind Message kind. One of the Thread::KIND_*
 	 * @param string $message Message body
-	 * @param string|null $from Sender name
-	 * @param int|null $opid operator id. Use NULL for system messages
-	 * @param int|null $time unix timestamp of the send time. Use NULL for
-	 * current time.
-	 * @return int|boolean Message ID or boolean false on failure.
+	 * @param array $options List of additional options. It may contain
+	 * following items:
+	 *  - 'name': string, name of the message sender.
+	 *  - 'operator_id': int, ID of the operator who sent the message. For
+	 *    system messages do not set this field.
+	 *  - 'created': int, unix timestamp of the send time. If you want to set
+	 *    current time do not set this field.
+	 *  - 'plugin': string, name of the plugin which sent the message. If
+	 *    message was not sent by a plugin do not set this field.
+	 *  - 'data': array with arbitrary data related with message. This value
+	 *    will be converted to array and serialized before save. If there is no
+	 *    such data do not set this field.
+	 *
+	 * @return int Message ID
 	 *
 	 * @see Thread::KIND_USER
 	 * @see Thread::KIND_AGENT
@@ -774,39 +789,11 @@ Class Thread {
 	 * @see Thread::getMessages()
 	 * @see Thread::postPluginMessage()
 	 */
-	public function postMessage($kind, $message, $from = null, $opid = null, $time = null) {
-		// Check message kind. It can not be equal to Thread::KIND_PLUGIN
-		if ($kind == self::KIND_PLUGIN) {
-			trigger_error(
-				'Use Thread::postPluginMessage to send plugins messages',
-				E_USER_WARNING
-			);
-			return false;
-		}
+	public function postMessage($kind, $message, $options = array()) {
+		$options = is_array($options) ? $options : array();
 
 		// Send message
-		return $this->saveMessage($kind, $message, $from, $opid, $time);
-	}
-
-	/**
-	 * Send plugin messsage
-	 *
-	 * @param string $plugin Plugin name. Use to determine which plugin sent
-	 * the message.
-	 * @param array $data Message data. Can contain arbitrary structure.
-	 * @param int|null $time unix timestamp of the send time. Use NULL for
-	 * current time.
-	 * @return int Message ID
-	 *
-	 * @see Thread::getMessages()
-	 */
-	public function postPluginMessage($plugin, $data, $time = null) {
-		$message = serialize(array(
-			'plugin' => $plugin,
-			'data' => $data
-		));
-
-		return $this->saveMessage(self::KIND_PLUGIN, $message, null, null, $time);
+		return $this->saveMessage($kind, $message, $options);
 	}
 
 	/**
@@ -814,10 +801,19 @@ Class Thread {
 	 *
 	 * @param int $kind Message kind. One of the Thread::KIND_*
 	 * @param string $message Message body
-	 * @param string|null $from Sender name
-	 * @param int|null $opid operator id. Use NULL for system messages
-	 * @param int|null $time unix timestamp of the send time. Use NULL for
-	 * current time.
+	 * @param array $options List of additional options. It may contain
+	 * following items:
+	 *  - 'name': string, name of the message sender.
+	 *  - 'operator_id': int, ID of the operator who sent the message. For
+	 *    system messages do not set this field.
+	 *  - 'created': int, unix timestamp of the send time. If you want to set
+	 *    current time do not set this field.
+	 *  - 'plugin': string, name of the plugin which sent the message. If
+	 *    message was not sent by a plugin do not set this field.
+	 *  - 'data': array with arbitrary data related with message. This value
+	 *    will be converted to array and serialized before save. If there is no
+	 *    such data do not set this field.
+	 *
 	 * @return int Message ID
 	 *
 	 * @see Thread::KIND_USER
@@ -829,22 +825,42 @@ Class Thread {
 	 * @see Thread::KIND_PLUGIN
 	 * @see Thread::getMessages()
 	 */
-	protected function saveMessage($kind, $message, $from = null, $opid = null, $time = null) {
+	protected function saveMessage($kind, $message, $options = array()) {
 		$db = Database::getInstance();
 
-		$query = "INSERT INTO {chatmessage} " .
-			"(threadid,ikind,tmessage,tname,agentId,dtmcreated) " .
-			"VALUES (:threadid,:kind,:message,:name,:agentid,:created)";
+		// Add default values to options
+		$options += array(
+			'name' => null,
+			'operator_id' => 0,
+			'created' => time(),
+			'plugin' => '',
+			'data' => array()
+		);
+
+		// Prepare message data
+		$options['data'] = serialize((array)$options['data']);
+
+		// Prepare query
+		$query = "INSERT INTO {chatmessage} (" .
+				"threadid, ikind, tmessage, tname, agentId, " .
+				"dtmcreated, plugin, data" .
+			") VALUES (" .
+				":threadid, :kind, :message, :name, :agentid, " .
+				":created, :plugin, :data" .
+			")";
 
 		$values = array(
 			':threadid' => $this->id,
 			':kind' => $kind,
 			':message' => $message,
-			':name' => ($from ? $from : NULL),
-			':agentid' => ($opid ? $opid : 0),
-			':created' => ($time ? $time : time())
+			':name' => $options['name'],
+			':agentid' => $options['operator_id'],
+			':created' => $options['created'],
+			':plugin' => $options['plugin'],
+			':data' => $options['data']
 		);
 
+		// Execute query
 		$db->query($query, $values);
 		return $db->insertedId();
 	}
diff --git a/src/messenger/webim/libs/classes/thread_processor.php b/src/messenger/webim/libs/classes/thread_processor.php
index 51a67b6e..c7a60b5b 100644
--- a/src/messenger/webim/libs/classes/thread_processor.php
+++ b/src/messenger/webim/libs/classes/thread_processor.php
@@ -326,11 +326,17 @@ class ThreadProcessor extends ClientSideProcessor {
 
 		// Set fields
 		$kind = $args['user'] ? Thread::KIND_USER : Thread::KIND_AGENT;
-		$from = $args['user'] ? $thread->userName : $thread->agentName;
-		$opid = $args['user'] ? null : $operator['operatorid'];
+		if ($args['user']) {
+			$msg_options = array('name' => $thread->userName);
+		} else {
+			$msg_options = array(
+				'name' => $thread->agentName,
+				'operator_id' => $operator['operatorid']
+			);
+		}
 
 		// Post message
-		$posted_id = $thread->postMessage($kind, $args['message'], $from, $opid);
+		$posted_id = $thread->postMessage($kind, $args['message'], $msg_options);
 
 		// Update shownMessageId
 		if($args['user'] && $thread->shownMessageId == 0) {
@@ -498,7 +504,7 @@ class ThreadProcessor extends ClientSideProcessor {
 			$posted_id = $thread->postMessage(
 				Thread::KIND_USER,
 				$first_message,
-				$visitor['name']
+				array('name' => $visitor['name'])
 			);
 			$thread->shownMessageId = $posted_id;
 			$thread->save();
@@ -621,7 +627,7 @@ class ThreadProcessor extends ClientSideProcessor {
 				getstring2('chat.visitor.info', array($info))
 			);
 		}
-		$thread->postMessage(Thread::KIND_USER, $message, $name);
+		$thread->postMessage(Thread::KIND_USER, $message, array('name'=>$name));
 
 		// Get email for message
 		$inbox_mail = get_group_email($group_id);
diff --git a/src/messenger/webim/libs/invitation.php b/src/messenger/webim/libs/invitation.php
index 0fd0f9c5..64592889 100644
--- a/src/messenger/webim/libs/invitation.php
+++ b/src/messenger/webim/libs/invitation.php
@@ -122,8 +122,10 @@ function invitation_invite($visitor_id, $operator) {
 	$thread->postMessage(
 		Thread::KIND_AGENT,
 		getlocal("invitation.message"),
-		$operator_name,
-		$operator['operatorid']
+		array(
+			'name' => $operator_name,
+			'operator_id' => $operator['operatorid']
+		)
 	);
 
 	return $thread;