Nexenta (OpenSolaris kernel) + VirtualBox [weird host crashes]

I don't suppose anyone has experienced any weird host crashes in Nexenta (host) using VirtualBox 3.0.x (in headless mode)?

It seems the host stays alive (I can even type text into the box if I have a keyboard hooked up) but it drops all user connections and network connections (so i can't ssh / ping it. I can't even log in using the direct keybaord connection).

Most infuriating as VMWare doesn't support OpenSolaris and I can't seem to get Xen running so I'm stuck with VBox