Reverse Proxing non web content

What is the best product to perform rever proxying on non web content. This is more like trying to publish a server in the internal network to external users using a different name and IP address but proxy server will name and IP queries to match IP/name details of internal sever and forward request accordingly. I have used Microsoft ISA server and IT DOESN’T WORK!!.
A document on how to configure whatever product is recommended will be appreciated.