Nevermind the last question: i found the answer here: http://www.gnutellaforums.com/showth...threadid=11915

all i did was
1. I actually uninstalled my old runtime for a newer version (this wasn't necessary, i just wanted the most recent version)
2. i typed the commands

export JAVA_HOME=/usr/java/j2re1.4.1, export PATH=$PATH:/usr/java/j2re1.4.1/bin
sh LimeWireLinux.bin

I have no idea what that did, but it worked

Thanks anyway