Per a recent commit, [url= http://marc.theaimsgroup.com/?l=openbsd-cvs&m=113390869003580&w=2 ]http://marc.theaimsgroup.com/?l=openbsd-cvs&m=113390869003580&w=2[/url] , to OpenBSD the next version of OpenSSH will support tun(4) forwarding. An excerpt, "This is a simple and easy way to use OpenSSH for ad hoc virtual private network connections, e.g. administrative tunnels or secure wireless access."
Support for this would obviate the need for IPSec or OpenVPN.

thanks