Forward GRE over NAT to firewall

[rasoftware]

I have a 1800 router at the network perimeter with a public address and private on the inside. Behind that I have a PIX with a private address on the outside interface. PIX uses the router as a gateway. I have a problem in that I can't forward PPTP/GRE traffic through to the PIX. I add port forward 1723 TCP/UDP on the router to the PIX but this doesnt seem enough. I also need GRE I guess which is portless. I manaage to create inound IPSEC tunnels because I can map UDP 500 and encap 4500 UDP. Does anyone know how to do the same for inbound PPTP tunnels?

Thanks

[ekiriakos]

have a look at this post. It gives you the router config.

http://forum.cisco.com/eforum/servlet/NetProf?page=netprof&forum=Network%20Infrastructure&topic=WAN%2C%20Routing%20and%20Switching&CommCmd=MB%3Fcmd%3Ddisplay_location%26location%3D.1dd9c3a5

HTH

E.