[pptp-server] Win95 Client not connecting to NT4 VPN Server behind RH6.2 Firewall

[Peter Rendle]

I have a very perplexing problem getting a Windows 95 client connected
to the Internet to connect via PPTP to a NT4 server behind a MASQ
firewall.  The firewall is running RH6.2 with kernel 2.2.16-12 which has
the ip_masq_pptp patch applied. (and module is loaded) I am using
ipmasqadm to forward port 1723 to the NT server.  I also have ipfwd
running for protocol 47.

The client machine appears to connect and I get a :
ip_masq_gre(): creating GRE masq for 10.0.0.2 -> xxx.xxx.xxx.xxx CID=0
MCID=5890
from syslog.
It then sticks on "Verifying username and password..." and eventually
comes back with a "Error 650: The computer you're dialing in to does not
respond to a network request." 

The big mystery is that a Windows 2000 client can connect with no
problems at all using the same ISP and username/password.

Please Help!