We are using Microsoft Live Communication Server and have users who log in via Cisco VPN and have problems with maintaining IM sessions with other LCS users. Within the ASA 5520 I have disabled SIP inspection. Users intermittently lose connections within their LCS sessions via VPN. Most of the users have Cisco client 4.6.x, some have 4.8.x. All other applications work ok within the VPN session. Has anyone else experienced this issue with Microsoft LCS? Are there any other config parameters that should be set within VPN?