Not sure if you updated Java recently but it's caused problems for several people. Your answer might be re-installing Java: Apple - Downloads - Application Updates - Java for Mac OS X 10.5 Update 4 & then do a Safe reboot & repair permissions then reboot normally.

How to do a Safe Boot? = Hold down SHIFT key whilst Booting up until you see the apple icon. You will then be required to login. Open Disk Utility found in Utilities folder & repair permissions on OSX. Then reboot normally.

If still problems install the beta version of LW: LimeWire 5.2.2 (Beta) - Lime Wire (if you are using LW 5 I mean.)

Okay, the Java/Safeboot thing didn't work, but the Beta LW did. Not sure what the difference is with Beta, but it works, so that's all I care about. Thank you!!!! My life can continue as normal.

Neither of the suggestions has worked for me. How do we revert to the previous java release? Limewire does not run with todays update. And why is it necessary to repair permissions?