help with role not working ??

We have a role called r_webusr. That role has execute permissions to a stored procedure called wdv_match. If I log into a sql session as myself, set the role to r_webusr, check to ensure the role is set, and execute the procedure I get a 668 error, ( cannot execute system command) btw, the procedure is using the system command to call a shell script. This is working in production, but not in dev any longer. It works when I run it as the owner of the procedure, but not as the role. Any ideas would be appreciated. thanks, floyd ps. ids10.0.FC5 on Aix5.3.