Checkpoint Secureclient VPN Access through TMG 2010?

Hi,

We have TMG standard 2010 for wireless internet access using Radius authentication.  Some of our users using Laptop and accessing Checkpoint secure client VPN to connect Client location. But  its not happening, We are getting the error of "gatway not responding. connection failed".

Kindly let me know any changes needs to done in firewall or web proxy access policy