Debugging Stored Procedures

I've been trying to get the debugger up and running per section 3.10.1
of http://www.redbooks.ibm.com/abstracts/sg246503.html.



I have been successful at stepping through stored procedures with no
parameters, however when calling a stored proc with an IN parm of
Integer type, the debugger throws an exception on the first line of the
stored procedure:



"Exception: Pointer not set for location referenced"



This is how I call the stored procedure:



CALL PGM(AMFLIB/TEST_DBG_2) PARM(13000)



Also, how would I call a stored procedure with IN and OUT parms from the
console?



Procedure:

CREATE PROCEDURE AMFLIB . TEST_DBG ( IN CUSTNUMBER INTEGER ) RESULT SETS
1 LANGUAGE SQL SPECIFIC TEST_DBG_2 READS SQL DA

SOURCE

BEGIN

DECLARE TOTALACTIVITY DECIMAL ( 8 , 3 );

SELECT SUM ( JQGLVA ) INTO TOTALACTIVITY FROM AMFLIB . MTHACTE WHERE
CUSNO = CUSTNUMBER;

END;