Cursors removed with commit

Hello,

I have a problem with my huge database ; using cursors (so using a transaction with noautocommit, statement with
type_forward_only)make cursors removed if I update and save (commit) database values in the same transaction during the
fetchloop. 

Error message is : portal "C_03" doesn't exist

All is fine if the commit is done in a different transaction.

In more details, in the statement creation :
  con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY, ResultSet.HOLD_CURSORS_OVER_COMMIT);
the last parameter seems to have no effect ... ?


Best Regards,
Christophe