VPN Problem with Exchange 2000 and MSN Messenger

[rob]

I have a client using Exchange 2000 with the Instant Messaging option over a VPN connection. The connection is a PIX-to-PIX VPN and both are running 6.0(1).

The only thing not working over the VPN connection is this issue with Messenger/Exchange: On the local LAN (where the Exchange server is) a user can send/receive IM's to users on the same LAN just fine.

We can also receive IM's from a user on the remote LAN, but we can't send IM's to users on the remote LAN.

Any idea why I can't send IM's to users on the remote LAN over a VPN connection?

[p.krane]

I’ve seen a few other posts about this. I use two other messengers across the VPN and they work fine so it seems to be an MSN Messenger issue. You probably better call Cisco to see if they can help but come back and let us know what you determine.