Here is an tested example which works on Squirrel with a db2 stored procedure . The trick is to passe with an transitional stored procedure MY_PROC_TEST to call the real stored procedure PROC_TEST.

change statement separator in squirrel > session > session properties > SQL : '@'

DROP PROCEDURE MY_PROC_TEST()@
CREATE PROCEDURE MY_PROC_TEST()
RESULT SETS 1 -- out resultset (call product)
LANGUAGE SQL
BEGIN
  DECLARE flag SMALLINT; -- out parameter
  CALL MY_PROC('2015', flag);
END @
CALL MY_PROC_TEST()@
END @

Then you can call the sored procedure like this :

CALL MY_PROC_TEST()@

Here is an tested example which works on Squirrel 3.7 with a db2 stored procedure . The trick is to passe with an transitional stored procedure MY_PROC_TEST to call the real stored procedure PROC_TEST.

change statement separator in squirrel > session > session properties > SQL : @

DROP PROCEDURE MY_PROC_TEST()@
CREATE PROCEDURE MY_PROC_TEST()
RESULT SETS 1 -- out resultset (call product)
LANGUAGE SQL
BEGIN
  DECLARE flag SMALLINT; -- out parameter
  CALL MY_PROC('2015', flag);
END @
CALL MY_PROC_TEST()@
END @

Then you can call the sored procedure like this :

CALL MY_PROC_TEST()@