Hmmm I run LimeWire Pro 4.4.5 and JRE 1.5.0_01 and don't seem to be having in problems.

I see you all are having problems, but I see very little information provided other than your running WindowsXP.

How about a little more information:
Computer type & CPU
RAM
HDD
what sp do you have installed.
LimeWire Version and where you downloaded it from
Java Version
Firewalls
Modem type & model
Connection Type (DSL,ADSL,Cable,Dialup)

You should take the time to read some of the stickies(ie. Newbies Guide to writing a good thread.)

It's hard to get answers or help when you don't provide the information needed.