amule uses gnutella network and doesn't need java.
To help you understand what limewire is lookin for...
type
echo $PATH at the cmd line this will display what is in your "path" where programs are allowed to execute from.
typicly /usr/bin/ /usr/share/ and so on.
To add java to your path you need to edit your .profile or .bash_profile and add the full path to java in the section that looks like the output from your echo $PATH command. To make this a system wide change you can add this to /etc/profile as root.
make a backup of whatever you edit in case you need to back out of the cange.
cp -p /etc/profile /etc/profile.origI can eloborate if this is too confusing or if you care.

I'd use amule I like it better anyway,