Listener-thread errors

We are running IDS 7.31.UD5 on SCO OpenServer 5.0.5. We have a recurring problem when approaching 128 active user threads. We begin to see the following in our logs: 11:00:28 listener-thread: err = -27001: oserr = 0: errstr = : Read error occurred during connection attempt. At this point, generally anyone who is already logged into the database can still work, but the system will not accept additional logins. The only way I have found to clear this error is to bounce the engine. Technical support for Informix is provided by our application vendor and, as yet, they have been unable to cure the problem. We are a relatively small company and, as such, I'm sure there are those of you with substantially larger databases (not to mention user bases) supporting many more concurrent user threads. I'm not sure if it matters, but our back-end applications are on a separate box running Windows 2000 Server. The database and application servers both have gigabit NIC's and reside on the same gigabit switch. Any ideas are appreciated. Chuck Johnson Practice Management Systems Administrator Morris Polich & Purdy LLP *******CONFIDENTIALITY NOTICE******* *****PRIVILEGED AND CONFIDENTIAL INFORMATION***** The information contained in this document is intended solely for use By the persons or entities identified above. This electronically transmitted document contains privileged and confidential information including information which may be protected by the attorney-client and/or work product privileges. If you are not the intended recipient, be aware that any disclosure, copying, distribution or other use of the contents of this transmission is prohibited. If you received this transmission in error, please notify us by telephone (213-891-9100) and permanently delete this message without making a copy.