[arch-general] The principle behind MSN & Yahoo invisible scanners?

[Nilesh Govindarajan]

  Go to google.com and search for MSN & Yahoo invisible scanners.
You'll find a big list.

So what's the principle of their working?
I'm thinking of writing a pidgin plugin to catch invisible buddies.

-- 
Regards,
Nilesh Govindarajan
Facebook: http://www.facebook.com/nilesh.gr
Twitter: http://twitter.com/nileshgr
Website: http://www.itech7.com
VPS Hosting: http://www.itech7.com/a/vps