I struggled with Java Invocation Error Messages and could not launch LimeWire on a G3 FireWire Pismo that had worked fine....until I unistalled OSX from the machine. Then LimeWire would not open.
The answer probably lies deep within the kernel of OS9 and shared code of OS 9 and X.
I am not sure whether the version that had been installed was an OS9 or X one.
I have since initialized a new hard drive and reinstalled OS 9.1. I am not intending to use OS X concurrently. I will run that on another machine once 10.2 arrives 'late Summer' according to Apple(no doubt September 20 at 11:59:59pm).
And I have installed LimeWire 1.7c. It works exceptionally with no Java exceptions!
The OSX version of LimeWire is just excellent by all accounts iff you are using OS X. I found the latest version 2.4 for OS9 to be very sluggish on my G3 500 Mhz with very slow redraw. It reminded me of trying to use the AOL Browser back when I had a Color Classic. Ugggh.
So I would recommend you backup your drive onto a friends or external hard drive, wipe disk with Norton and reinstall OS9.1 - and download an earleir version of LimeWire.
And use Norton Disk Doctor and Speed Disk nightly when you first start downloading files. I had 'Major Problems Found' results when my MP3s appeared with NO icon! Initially they had appeared with a QuickTime Icon even though I have iTunes. The 'Error' was related to the Hard Drive not knowing where to put files. I just discovered the 'File Exchange' control panel and it's applications thanks to some posts in this forum.
Remember we are dealing with magnetic impulses on small round metal discs spinning hundreds of times per minute. It's not perfect. Patience and determination serve us well in the long run. And reading this forum and supporting the developers at LimeWire.

G.