Are you going through a vpn tunnel. This could be an mtu issue. There may have been something in the design (the way the other firewall was configured and how the actual physical layout was done) that the mtu issue couldn't occur.
At the remote workstation, try:
ping -f -l 1400 to the outside public IP of the firewall. If it says df bit set...lower it to 1200, 1100, 1000....lower it till your pings make it to the firewall.
Then change the mtu of your workstation to that level....ie. packet size of 800 if that is what got through. Cisco vpn client has a built in tool to easily do this....or search the web. Then try an ssl connection.
Cheers,
Jim