http://www.mars.org/home/rob/proj/hfs/
I don't have anything to test on but will this work? It says it won't do it on HFS+. It's made for unix but there ports to windows.

But if I'm reading this right BOOO. Did you check the OpenBSD site first.
http://www.openbsd.org/3.5_packages/....tgz-long.html