can't use Cisco vpn client to connect through TMG 2010

Hello

We've encountered a problem with TMG where we can no longer connect to a client of ours using a Cisco VPN client through the new TMG. The connection errors out with a reason 412: the remote peer is no longer responding.

strangely enough when trying to establish this connection I don't see any traffic going through the TMG server. I've set access rules to allow all traffic from this computer to the outside world and still no luck...am wondering if this is a known issue with ipsec tunnels?

Thanks

Bryan