I had a little trouble installing Limewire on Mandrake 10 myself. It couldn't seem to find my Java installation on it's own. Putting a symlink to the Java executable file in my bin directory seemed to fix the problem. Doing this in a bash shell should look something like:

user$ ln -s /your_java_directory_pathway/executable_file link_name

for me the line was:

user$ ln -s /usr/java/j2re1.4.2_05/bin/java java

I hope this helps.