I'm looking for a step-by-step howto for setting up an Openbsd ipsec tunnel between 2 OpenBSD boxes and another configuration of having and OpenBSD box act as a VPN concentrator and having a WindowsXP client go through that.

I see a variety of ones on the net, but it seem that they are for previous version of openbsd, which in turn usually ends up missing something.

So, can anyone recommend a particular tutorial for this subject?