Index: /CKEditor/branches/features/bbcode/_source/plugins/entities/plugin.js
===================================================================
--- /CKEditor/branches/features/bbcode/_source/plugins/entities/plugin.js	(revision 6744)
+++ /CKEditor/branches/features/bbcode/_source/plugins/entities/plugin.js	(revision 6745)
@@ -135,6 +135,6 @@
 				var entitiesTable = buildTable( selectedEntities );
 
-				// Create the Regex used to find entities in the text.
-				var entitiesRegex = '[' + entitiesTable.regex + ']';
+				// Create the Regex used to find entities in the text, leave it matches nothing if entities are empty.
+				var entitiesRegex = entitiesTable.regex ? '[' + entitiesTable.regex + ']' : 'a^';
 				delete entitiesTable.regex;