Faulty error handling in DBPROC, MAXDB version 7.8.02.35

I have an update statement which gives an error thus :

UPDATE BOSS.T_TESTS

SET VERSION = VERSION + 1

WHERE ID = 1148

AND VERSION = 0

Error Executing 'UPDATE BOSS.T_TESTS SET VERSION = VERSION + 1 WHERE ID = 1148 AND VERSION = 0' SAP DBTech JDBC: [-3018]: Invalid numeric parameter

The error occurs because the update trigger for the table calls a procedure which has faulty code. So, I want the error to occur.

However, if I put my update statement in a dbproc like this :

CREATE DBPROC UPDATE_TEST (IN ID INTEGER, IN TEST_DATE DATE, IN REFERENCE VARCHAR (50), IN COMMENTS VARCHAR (500), IN VERSION INTEGER, INOUT NEWVERSION INTEGER) AS

TRY

    UPDATE BOSS.T_TESTS

    SET    TEST_DATE = :TEST_DATE,

        REFERENCE = :REFERENCE,

        VERSION = VERSION + 1

    WHERE    ID = :ID

    AND        VERSION = :VERSION ;

CATCH

        STOP ($RC, $ERRMSG) ;

//

and call it like this :

create dbproc test as

VAR

    COUNT    INTEGER ;

    OCL        INTEGER ;

call boss.update_test (1148, '2014-09-08', 'jl/109', '', 0, :ocl);

insert into boss.x values (:ocl);

//

call test

I get

Statement 'call test' successfully executed in 170 ms

The same error is occurring - the update has not succeeded - but the error message is not reported.

Is there a workaround or has this been fixed in later DB versions?