It happens that I bought Parallels 5 two or three days ago. Upon
upgrading my
Plan 9 VM from Parallels 3 (skipped a version), it stopped working.
I've not had
time to dig in, nor to try a fresh install. The Plan 9 version on
there had not been
kept up to date, so Geoff's info is likely more reliable.
This was on OS X with Parallels Desktop.
I've heard nothing but bad things about VirtualBox. Mostly from Plan 9
people
(where the results have been uniformly bad), but also from folks
trying to use
other OSes. It seems the worst of the breed across the board.
Anthony