How to call a maxdb procedure from ireport with error: SQL-Statement would generate a row count

Hello Everybody

I need to call a dbprocedure with iReport5.5 to get a new Barcode from an "SAP MaxDb" database.

No success :-(

This is the definition for the database:

CREATE  DBPROC SERVOY_AUTONUM  (IN SUCHKEY CHAR(30),OUT NEUERWERT FIXED(10,0)) AS

BEGIN

SELECT   WERT INTO :neuerwert FROM "BWALLE"."AUTONUM"  WHERE SUCHBEGRIFF     =:suchkey WITH LOCK EXCLUSIVE;

IF $RC = 0 THEN

BEGIN

UPDATE  "BWALLE"."AUTONUM" SET WERT = WERT + 1 WHERE SUCHBEGRIFF     = :suchkey ;

SET NEUERWERT = NEUERWERT + 1;

END

ELSE

     SET NEUERWERT = - 1;

END;

The procedure returns just a new mumber!

From Visual Foxpro we call it like this:

l_suchbegriff = "TEST"

neuerwert = 0

CALL SERVOY_AUTONUM(?l_autosucher,?@neuerwert) WITH COMMIT

From SQL Studio we call it like this:

call SERVOY_AUTONUM ('TEST',?) with commit

From our web development tool we call it like this:

var suchbegriff = "TEST"

function g_autonum('suchbegriff) {

    // wir rufen die datenbank procedure servoy autonum mit einem Suchbegriff

    var procedure_declaration = "{CALL BWALLE.SERVOY_AUTONUM(?,?)}"

    var args = [suchbegriff, java.sql.Types.NUMERIC];

    var argTypes = [0, 1]; //0 = input 1 = output

    try {

        var dataset = plugins.rawSQL.executeStoredProcedure('maxdb', procedure_declaration, args, argTypes, 1);

        if (plugins.rawSQL.getException()) {

        ...

        }

    } catch (e) {

        application.output(e);

    }

    var v_neueid = dataset.getValue(1, 1);

    return v_ergebnis;

}

Until now i found now way to call this procedure from IReport.

following the examples I tried:

call BWALLE.SERVOY_AUTONUM($P{Suchbegriff}, $P{ResultSet})

and got a error message:

SQL-Statement would generate a row count ???

Did someone ever called a maxdb procedure from IReport? (Example?)

Any help welcomed.

Best regards

Albert