I had this working in Mandrake 9! This is RedHat 7.3. I also redownloaded the installer and installed JRE 1.3.1-06 with EXACTLY THE SAME ERROR MESSAGE. No, I have not installed Blackdown or Kaffee or anything but Sun's JREs.

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[cdevidal@localhost linux]$ rpm -q j2re
j2re-1.4.1_01-fcs
[cdevidal@localhost linux]$ export PATH=/usr/java/j2re1.4.1_01/bin:$PATH
[cdevidal@localhost linux]$ java -version
java version "1.4.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_01-b01)
Java HotSpot(TM) Client VM (build 1.4.1_01-b01, mixed mode)
[cdevidal@localhost linux]$ ./LimeWire-2.8.4.bin
Preparing to install...
Extracting the installation resources from the installer archive...
Configuring the installer for this system's environment...

Launching installer...

Exception in thread "main" java.lang.NoClassDefFoundError: com/zerog/lax/LAX
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???????
/dev/idal