MDO: SQL-Error with TimeStamp

Hello,

I'm dealing with MDO's - it's working fine but actually I have a problem with a TimeStamp-Field.

com.sap.xmii.Illuminator.logging.LHException: com.sap.sql.log.OpenSQLException: Failed to set the parameter 11 of the statement >>UPDATE MDO592 SET FIELD18 = ?,FIELD19 = ?,LASTQUERYEXECUTION = ?,LASTQUERYEXECUTIONBY = ? WHERE FIELD3 = ? AND FIELD16 = ? AND FIELD17 = ? AND FIELD6 = ? AND FIELD13 = ? AND FIELD5 = ? AND FIELD38 <= ?<<: Cannot assign an object of type >>java.lang.String<< to a parameter with JDBC type >>TIMESTAMP<<.

I've tried to assign a timestamp with "datenow" => same error.

Other case "datefromxmlformat(datenow, Query.DateFormat) => same error.

Any Ideas?

We are on MII 15.0, SP 4, Patch 13

Thank in advance.