IRC and mIRC never ever displayed a person's email address in their /whois information.

It would be by sheer coincidence, and classical UNIX computing, your ISP or University(ISP) had your IP address resolve to their corporate domain name, and your Ident would resolve to your account Username that was also your email address with the ISP or institution. But that would have always been pretty rare.

Maybe you're thinking about /ctcp Tiago finger



Well. At least I won lunch.
Good philosophy, see good in bad, I like!