I think the best way would be to rewrite the beast using the categories package now, but I'm not sure. Furthermore, this would require a thorough rewrite, and I'm not even sure this is useful. Not to mention the hell of an upgrade script.
As I'm not able to tune bug-tracker, we have a couple of options:
a) Delay the upgrade til someone tuned bug-tracker
b) Upgrade but leave bugtracker on the old openacs.org
Last but not least, a maybe heretic question: How about tanking bug-tracker altogether for openacs.org and make use of sourceforge (for the bug-tracking)?
Though the last approach would mean we are not eating our own s*** anymore, it has a couple of advantages:
1) We could finally upgrade openacs.org
2) OpenACS would get great exposure on sourceforge