We have recently discovered a wonderful "feature" in the PIX at my office. Here's the scenario...
One person on our LAN connects from their laptop through our PIX and to a customer site using the Cisco VPN client.
Another person on our LAN tries to connect from their laptop through our PIX and to the same or different customer site using the Cisco VPN client. This second person is unable to connect.
Once the first person has disconnected for 10 minutes (the xlate cache?) then the next person can connect to the customer site.
Maybe it's something simple, or a limitation on the PIX, or a configuration change that needs to be made, but it drives us crazy here.
We have a PIX 515R with 6.3.4 running on it.