Index: /CKEditor/trunk/_source/plugins/showblocks/plugin.js
===================================================================
--- /CKEditor/trunk/_source/plugins/showblocks/plugin.js	(revision 3712)
+++ /CKEditor/trunk/_source/plugins/showblocks/plugin.js	(revision 3713)
@@ -127,4 +127,11 @@
 
 			// Refresh the command on setData.
+			editor.on( 'mode', function()
+				{
+					if ( command.state != CKEDITOR.TRISTATE_DISABLED )
+						command.refresh( editor );
+				});
+
+			// Refresh the command on setData.
 			editor.on( 'contentDom', function()
 				{