public function listServerTokens ( $user_id )
	{
		
                $sql = "BEGIN SP_LIST_SERVER_TOKENS(:P_USER_ID, :P_ROWS, :P_RESULT); END;";

                // parse sql
                $stmt = oci_parse($this->conn, $sql) or die ('Can not parse query');

                // Bind In and Out Variables                
                oci_bind_by_name($stmt, ':P_USER_ID', $user_id, 40);
                oci_bind_by_name($stmt, ':P_RESULT', $result, 20);

                //Bind the ref cursor
                $p_row = oci_new_cursor($this->conn);
                oci_bind_by_name($stmt, ':P_ROWS', $p_row, -1, OCI_B_CURSOR);

                //Execute the statement
                oci_execute($stmt);

                // treat the ref cursor as a statement resource
                oci_execute($p_row, OCI_DEFAULT);
                oci_fetch_all($p_row, $listServerTokensList, null, null, OCI_FETCHSTATEMENT_BY_ROW);
                $ts = $listServerTokensList;
		return $ts;
	}