problems with system call from with a stored proceudre (On-line 5.02uc7)

I am having difficulties using stored procedure under Informix On-line ver 5.02 uc7. When I use the system '' command, the program being called works fine (returns 0). However Informix reports that a -668 (system command cannot be executed) Error has occurred . If the stored proc. is ran from with in dbaccess, dbaccess reports the -668 error along with a messages stating something to the effect of not being the owner (of what I'm not sure). Anyway I have contacted Informix, and they are looking into it (there tech support has always been quite good, but this is really messing up a programming effort with a tight deadline). Permissions should not be the problem (owner ship might be ??) everything is wide open. The procedure is being invoked by a trigger (I've tried calling the procedure directly with the save results). The procedure is trivaly in nature; nothing is really done other than the system call with parms that were passed to the stored proc. Who should be the owner of programs called via a system call (I've tried the database owner and root, to not avail) ? Has anyone successfully used stored procedures with a system call with this version of Informix??