Index: units/languages/languages_item.php
===================================================================
--- units/languages/languages_item.php	(revision 14103)
+++ units/languages/languages_item.php	(working copy)
@@ -39,6 +39,10 @@
 			// in case, when Update method is called for this langauge object
 			$this->SetDBField($primary_field, 1);
 			$this->SetDBField('Enabled', 1);
+
+			// increment serial by hand, since no Update method is called
+			$this->Application->incrementCacheSerial($this->Prefix);
+			$this->Application->incrementCacheSerial($this->Prefix, $this->GetID());
 		}
 
 		/**