diff --git a/phpgwapi/inc/class.schema_proc.inc.php b/phpgwapi/inc/class.schema_proc.inc.php
index 3fa6bf9c5d..7163ac475b 100644
--- a/phpgwapi/inc/class.schema_proc.inc.php
+++ b/phpgwapi/inc/class.schema_proc.inc.php
@@ -1426,7 +1426,7 @@ class schema_proc
 							// for PostgreSQL we dont use length-limited indexes --> nothing to do
 							if ($this->m_odb->Type == 'pgsql') continue;
 							// for MySQL we drop current index and create it with correct length
-							$this->DropIndex($table, $definition);
+							$this->DropIndex($table, $columns);
 						}
 						$this->CreateIndex($table, $columns, $type == 'uc');
 					}