I havn't had a chance to test this out fully. Here are some links and info which I have come across on this topic.
apt-get install openvpn
Configs are kept in /etc/openvpn/
Error message is: “Cannot open TUN/TAP dev /dev/tap0: No such file or directory (errno=2)”. Even if you enabled the TUN/TAP module in the kernel you have to: ( http://openvpn.net/archive/openvpn-users/2004-04/msg00136.html ) mkdir /dev/net mknod /dev/net/tun c 10 200 (Linux kernel 2.4.x)
Good Notes on Configing and generating client and server certs : http://deb.riseup.net/networking/openvpn/ <br>Look in /usr/share/doc/openvpn/examples/easy-rsa for making certs.
Good Debugging and solutions to errors: http://forums.gentoo.org/viewtopic.php?t=233080