Following my recent adventures with Azureus, I found that Azureus was crashing on a regular basis and often not starting up at all. Running it from the command line gave me an error similar to the following:
An unexpected error has been detected by HotSpot Virtual Machine
and a lot of mumbo-jumbo following that.
This error has been reported all over the place, including at bugs.sun.com (who decided to close it.. thanks guys! :S). But no apparent solution was being provided anywhere. Azureus was definitely stable when running 1.4.2, although it wasn't exactly performing up to par. So, this was definitely a java compatibility problem.
The eventual solution (if it can be called such) that I arrived at was of just deleting my .azureus profile, and recreating it. Prior to doing so, I made sure that I'd backed up my torrents directory (inside .azureus/), which allowed me to reinsert and resume my torrents quickly and easily.
Not much of a solution, but there it is.. It appears to have fixed the issue and I haven't had an Azureus crash for a few hours now.
Adios.
Edit:
Nope. That didn't fix it :/ However, I dug around a bit more and came up with a solution on a french ubuntu support site. The fix was to just replace the installed JAR file with the correct JAR file from Azureus' website. In other words, this was either an Azureus bug or a Debian / Ubuntu packaging bug.
Command line fix:
sudo wget http://superb-west.dl.sourceforge.net/sourceforge/azureus/Azureus2.5.0.0.jar
sudo mv Azureus2.5.0.0.jar /usr/share/java/Azureus2.jar