Copyright © 2008 Aaron Tindall All Rights Reserved
Port Forward is a Windows Service which forwards any arbitrary set of local ports to any other set of ports, local or remote. Information on port forwarding can be found here Wikipedia's port forwarding article
You can try Port Forward for 10 days to see if it works for your purposes before purchasing.
Current version is 1.01. Version 1.01 improves upon version 1.0 by packaging Sun's JRE 1.6 as well as correcting bug fixes.