RBVM BSD
OpenBSD
Tested on OpenBSD 4.5 i386
The switching off the irqchip setting allowed me to get the machine to boot, however, I couldn't get any working network interface with this set. There's another fix for this issue, documented here.
The default network card also doesn't work very well, set it to e1000 instead. The i8255i (fxp0) device seems to crash the vm when it tries to bring up the network.