I don't know -much- about Macs having only used them for design rather than looking at the OS... reinstalling Java should be as easy as re-downloading the EXE from sun.com and executing it. Aswell as uninstalling your current version of LW and possibly getting in contact with "Lord of The Rings" who has a backlog of releases and will be able to give you one which was working with your system but I'm sure he'll give you more information on switching back to an older release!

Just hold up if nothing else has worked so far... uninstall everything connected to limewire and reinstall it for now.

Seith