Try something like this:

Code:
--#SET TERMINATOR @

BEGIN
  IF NOT EXISTS (SELECT 1 FROM SYSCAT.TABLESPACES WHERE TBSPACE='USERSPACE2') THEN
    EXECUTE IMMEDIATE 'CREATE TABLESPACE USERSPACE2';
    CALL ADMIN_MOVE_TABLE(...);
  END IF;
  CALL ADMIN_CMD('REORG TABLE MYSCHEMA.MYTABLE');
END@