I had the same problem under RH 8.0. Being new to LInux, I had to fuss around with it forever to figure it out. In the end, this is all I had to do:

Edited my .bash_profile PATH statement to include the following: $HOME/j2re1.4.1_01/bin

That's where I installed the jre. Logged out and back in (not sure this is necessary), and the LimeWire installer loved it.