Interbase Stored Procedures

Hi when I run a script with a query that executes a stored procedure on the Interbase server I'm getting a warning. Warning: InterBase: message length error (encountered 0, expected 8) in C:\Programme\Apache Group\Apache\htdocs/wawi/bestellung.php3 on line 85 for the line $qry = ibase_query($db, "EXECUTE PROCEDURE SP_GETNEXTDOK (81, 2000);"); . But(!) the query has been executed correctly (I can see the results in the corresponding tables). The procedure SP_GETNEXTDOC should return an Integer value called NUMMER but interrupts with that warning. So far done: (1) The ";" has been removed and added (as above) - no better result (2) In Delphi exists a VCL-Component called TStoredProc that runs the procedure correctly (3) Yes, the name of the SP is correct... Configuration: PHP 3.0.16, Win32 (NT), Apache 1.3.12, Interbase 5.5 My questions: (1) Why does PHP throws that warning? (2) Is there a possibility to execute interbase stored procedures? (3) Are there alternatives (except ODBC) accessing Interbase through PHP3? TIA, Frank