LCS CWA: Communicator Web Access
Are you aware of Communicator Web Access?
Do you have non Windows OS systems without IM today (Macintosh, Linux/UNIX, or older Windows clients even)?
Do you have users traveling that use Kiosks to get e-mail?
https://www.microsoft.com/office/livecomm/communicator/webaccess/prodinfo/default.mspx
Look for another post on tracing entries to help diagnose problems (rather verbose)
TomL LCSKid