Most of the latest operating systems - Windows 8, MacOSX 10.8 are not packaged with Java. Looks like this might also be the case with the newer Linux releases?
Simply means you need to install Java yourself independently from the Java site.

Or am I misunderstanding your post?
It might be the same issue Windows users have had with any LW 5 version including LPE. ie: LW will not run directly with Java 7, you need to create a shortcut to the LimeWire.jar file http://www.gnutellaforums.com/connec...tml#post368753. I am not sure what are the equivalents for Linux.