Index: mysql-5.1-runtime/storage/innobase/handler/ha_innodb.cc
===================================================================
--- mysql-5.1-runtime.orig/storage/innobase/handler/ha_innodb.cc
+++ mysql-5.1-runtime/storage/innobase/handler/ha_innodb.cc
@@ -6387,6 +6387,7 @@ ha_innobase::external_lock(
 	int	lock_type)	/* in: lock type */
 {
 	trx_t*		trx;
+	ulint		error = 0;
 
 	DBUG_ENTER("ha_innobase::external_lock");
 	DBUG_PRINT("enter",("lock_type: %d", lock_type));
@@ -6484,13 +6485,13 @@ ha_innobase::external_lock(
 			    && thd_test_options(thd, OPTION_NOT_AUTOCOMMIT)
 			    && thd_in_lock_tables(thd)) {
 
-				ulint	error = row_lock_table_for_mysql(
+				error = row_lock_table_for_mysql(
 					prebuilt, NULL, 0);
 
 				if (error != DB_SUCCESS) {
 					error = convert_error_code_to_mysql(
 						(int) error, thd);
-					DBUG_RETURN((int) error);
+					goto err_cleanup;
 				}
 			}
 
@@ -6500,6 +6501,7 @@ ha_innobase::external_lock(
 		DBUG_RETURN(0);
 	}
 
+err_cleanup:
 	/* MySQL is releasing a table lock */
 
 	trx->n_mysql_tables_in_use--;
@@ -6535,7 +6537,7 @@ ha_innobase::external_lock(
 		}
 	}
 
-	DBUG_RETURN(0);
+	DBUG_RETURN((int) error);
 }
 
 /**********************************************************************