static function create( $workflowID, $typeString )
    {
        $row = array(
            "id" => null,
            "version" => 1,
            "workflow_id" => $workflowID,
            "workflow_type_string" => $typeString,
            "description" => "",
            "placement" => eZPersistentObject::newObjectOrder( eZWorkflowEvent::definition(),
                                                               "placement",
                                                               array( "version" => 1,
                                                                      "workflow_id" => $workflowID ) ) );
        return new eZWorkflowEvent( $row );
    }