We can establish a tunnel between the VPN client 3.5.1 and the PIX firewall from a remote address.
If we include split-tunnel functionality, connectivity with the internal network is lost. Removing split-tunnel from the config restores connectivity to the internal network and the VPN tunnel provides proper functionality.
However, these problems do not occur if the VPN client is on the same subnet as the outside interface of the PIX - split-tunnel works correctly.
Any suggestions?