tbspaces Access Control

I'm developing some automated testing scripts. I want to be able to start a database "from scratch", configure it, and then insert files prior to running the tests of interest. I'm hardly an Informix expert. I want the tests to be runable by an "ordinary" user. I don't want to run them as "root" or as "informix". I've been able to start Informix with a single rootdbs and populate the database. I encountered a problem when I tried to use "tbspaces" to add another table space on one or more disks. The "tbspaces" command insists that I have to be logged in as "informix" in order to use it. I wrote a set-uid program doInformix that is owned by user "informix". "doInformix command arg1 arg2 ..." runs the specified command, e.g. tbspaces, with an effective user-id of "informix". Running tbspaces this way still results in a "must be run by informix" message, which implies tbspaces is checking the real user ID (getuid()) and not the effective user ID (geteuid()). Is there any easy way to convince tbspaces to run for an ordinary user? Doing this wouldn't result in any DB safety problems since the DB will be discarded after the tests are run. Thanks, Barry