BlackIce only prohibits unsolicited information. If you are running LimeWire, it isn't exactly unsolicited. It won't prohibit any information passing from your computer. Look up the references to a push. Try a standard firewall leak test on it and it will fail.

If you want more information on firewall vulnerabilities check out these sites:

http://rr.sans.org/firewall/not_enough.php

http://grc.com/lt/leaktest.htm

All this came to light when GRC came under attack. They discribe it here but I have to warn you, it's lengthy.

http://grc.com/dos/grcdos.htm

Anyway, because you have limewire installed on your pc, it allows others to contact because they become "requested" information.

Yes, LimeWire is a true potential security threat along with most programs you install. (although limewire distrubes it's code so you could discern what it actually does, but I'm as likely to do that as carefully read licensing agreements)