BTW - One thing comes to mind that may not be standard. If you are running UCCX in a UCM 4.x (Windows Based CallManager) cluster then you will need to check the "Host" file on all the Subscribers and Publishers and Unity. Many installation techs were in the habit of adding every server to the Host files of every other server.
This will cause the greatest problem on the UCCX server itself, so start with that host file.
I have also seen Agent Desktop PC's with edited Host files.
If you are not familiar with this file, it is located at:
c:\winnt\system32\drivers\etc\host
Read this page for more info:
Configuring The IP Hosts File on a Windows 2000 CallManager Server [Cisco Unified Communications Manager (CallManager)] - Cisco Systems good luck