Nortel VPN Client through Cisco 1601 router - connection problem

[Scrye]

I have read many problems and solutions over the past week and most of the problems are similar to mine but I have not come across any solutions that I have not already tried.

My problem is:

When connecting to a customers VPN server I get the following message:

"Failed to get DNS & WINS configuration information through the Extranet Connection. Connection closed.

Usually this error indicates that a firewall is preventing IPSecurity packets from reaching the Extranet Switch."

I know it is the router access list that is the problem because when I turn the access list off I can connect. Although I am able to ping the VPN server with the access list on but cannot connect with Nortel VPN Client. The access list commands being used are:

access-list 100 permit ip xxx.xxx.xxx.xxx xxx.xxx.xxx.xxx host xxx.xxx.xxx.xxx
access-list 100 permit tcp xxx.xxx.xxx.xxx xxx.xxx.xxx.xxx host xxx.xxx.xxx.xxx
access-list 100 permit udp xxx.xxx.xxx.xxx xxx.xxx.xxx.xxx host xxx.xxx.xxx.xxx

To my understanding this will allow all ports open to a specified ip address from a range of ip addresses.

Any help would be greatly appreciated.