Hey, i have been having the same problem as you. When limewire starts everything is fine until 30 seconds into the thing my whole internet dies out on me. The LED lights on my modem and router are fine. Each time this happens i have to unplug the router and plug it back in. its getting very annoying. i've installed the latest java 1.6, uninstalled reinstalled limewire several times and also deleted the .limewire folder, but its still happening. here are my specs:

1. OS version? windows xp sp2
2. What firewalls you have? windows firewall
3. How much ram? 1gb
4. Hard Disk space available? 160gb
5. Connection type? cable
6. Modem & router brand name & model numbers? linksys wrt54g v5 wireless router. scientific atlanta cable modem.
7. Where are you trying to connect from? house
8. What version of LimeWire (LW) & Java do you have? LW 4.12.11 java 1.6.0
9. Who is your ISP provider (Internet Service Provider)? comcast
10. Do this simple test for us. Using your browser go here: http://www3.limewire.com:6346/ The page should say 'Your test worked!'. What happens when you go there? success
11. Are you sharing the connection with other computers or p2p sharing programs? If yes, please give details of set up.
1 desktop w/ LW, 1 notebook with LW. desktop connected directly to modem, laptop connected wirelessly.
12. Is this a your 1st try at LW or is this a new problem with an experienced user. new problem experienced user
13. Do you see a brick wall in front of the blue world icon at the bottom of LW's interface? no