diff --git a/src/mibew/js/source/default/handlebars_helpers.js b/src/mibew/js/source/default/handlebars_helpers.js
index 0311dd8c..bbfff4d9 100644
--- a/src/mibew/js/source/default/handlebars_helpers.js
+++ b/src/mibew/js/source/default/handlebars_helpers.js
@@ -56,7 +56,7 @@
     * This helper unescape HTML entities for allowed (span and strong) tags.
     */
     Handlebars.registerHelper('allowTags', function(text) {
-        var result = text;
+        var result = text.toString();
         result = result.replace(
             /<(span|strong)>(.*?)<\/\1>/g,
             '<$1>$2</$1>'
diff --git a/src/tests/client_side/qunit/test_cases/handlebars_helpers_tests.js b/src/tests/client_side/qunit/test_cases/handlebars_helpers_tests.js
index 5255a189..c8d88e35 100644
--- a/src/tests/client_side/qunit/test_cases/handlebars_helpers_tests.js
+++ b/src/tests/client_side/qunit/test_cases/handlebars_helpers_tests.js
@@ -108,6 +108,43 @@ test('urlReplace', function() {
     );
 });
 
+// Test "allowTags" Handlebars helper
+test('allowTags', function() {
+    var template = '{{allowTags foo}}';
+    var compiledTemplate = Handlebars.compile(template);
+    var escape = Handlebars.Utils.escapeExpression;
+
+    equal(
+        compiledTemplate({foo: escape('<span>The content</span>')}),
+        '<span>The content</span>',
+        'Test a tag without attributes'
+    );
+
+    equal(
+        compiledTemplate({foo: escape('<span class="red">The content</span>')}),
+        '<span class="red">The content</span>',
+        'Test a tag with class attribute'
+    );
+
+    equal(
+        compiledTemplate({foo: escape('<span data-foo="bar">The content</span>')}),
+        escape('<span data-foo="bar">The content</span>'),
+        'Test a tag with arbitrary attributes'
+    );
+
+    equal(
+        compiledTemplate({foo: 'content'}),
+        'content',
+        'Test not a tag'
+    );
+
+    equal(
+        compiledTemplate({foo: 456}),
+        '456',
+        'Test not a string argument'
+    );
+});
+
 // Test "nl2br" Handlebars helper
 test('nl2br', function() {
     var template = '{{nl2br foo}}';