Here is a strange one .. I have a VPN3030 Concentrator (Version 4.1.4) to which I am able to connect without issue. The problem is that traffic is flowing in only 1 direction (according to the client - version 4.0.3C) it flows in the transmit to the concentrator, but not the receive. My client is sitting behind a PIX 501. I have opened everything up on the PIX and it still behaves the same way. Now, when I bypass the PIX and run the PPPoE client on my laptop, it connects and traffic flows in both directions. I am troubleshooting this for a customer who is not using PIX everywhere - they have several Watchguard firewalls deployed and they behave in the same manner. One point of note is that this problem does not happen to everyone .. only a handful of users with nothing in common except for the concentrator.
If anyone has seen this or has any insight/suggestions, it would be greatly appreciated.