Single User Limit Exceeded in SE 7.1

We are running Informix SE 7.1 on SCO Unix 5.0. We have recently ported to SE from Online and are experiencing an occasional problem to which we need to find a better solution than completely reloading SE. When we ran Informix Online, sometimes we got the error 753 Single User Limit has been Exceeded. No other informix processes seemed to be running, and no other users were even logged in. Neither the application program nor dbaccess would run. Now that we've converted to SE, we occasionally get the same problem - error 753 Single User Limit has been Exceeded. Again, no other informix processes are running, and no other users are logged in. This time, the application program will run (but of course will not access the database), but dbaccess still won't run (error 753). So far the only solution we've been able to find is to completely reload Informix which is NOT the ideal solution, to say the least. We are getting ready to field hundreds of copies of the application throughout the U.S. to users who will not be capable of fixing this on their own. More details: The computer is a standalone 486 computer...not networked. We're using XWindows on one terminal (tty), and the application runs on that tty. We switch between terminals on the computer by CTRL-ALT-F1, CTRL-ALT-F2, etc. Normally we can run dbaccess from any tty, and the application from the CTRL-ALT-F2 terminal only. The only informix-related process that's running when we have the error is /usr/informix/lib/sqlexecd local_se. This is the same machine on which another problem reported to this newsgroup is occurring, a large degradation in performance. That question was submitted by mattaya@richmond.infi.net. Note to Michelle and anyone on the newsgroup who may be able to help...we were experiencing the degradation under Informix Online as well. I'm not an expert, but I don't think it's a problem with SE. Now that we've loaded SE on all our machines, we have no way of comparing, however. We're just comparing to the prior version which did not use Informix at all. If anyone can help, we'd all appreciate it greatly. We're in a big hurry! If you need more information to be able to help, please be specific with what more information you need. Thanks, Tricia White (kwhite@foto.infi.net) please also reply to mattaya@richmond.net and save the company a long distance call!