Just starting to play around with Eucalyptus, I've hit a few issues over the days - I've raised tickets when appropriate.
Anyhow, I've written up all my notes at http://smop.co.uk/mediawiki/index.php/Eucalyptus. I think there are some useful bits here for people - some fixes for when I'd missed a step or the instructions were unclear together with the troubleshooting and diagnostic steps I took.
HTH, I'm not a Java developer but I try and give back where I can!
Adrian