Not sure if it's already been suggested but I would love to be able to set different /whois info per network (or connection). This includes nickname, fullname and ident. Also if possible, firewall setting.

This can be scripted...
/help /server
look at the -i switch
and you can change firewall settings trough scripts w/ /firewall

on *:start: {
firewall plaa plaa plaa
server irc.server.com -i nick1 anick1 ident@mail.com fullname
firewall plaa plaa plaa
server -m irc.server2.com -i nick2 anick2 ident2@mail.com fullname2
etc...
}

I'm not against the suggestion, I'm just showing a way around the problem until the feature gets added to mIRC

Umm... what does any of the script you just posted have to do with displaying info in /whois?

Anyway, it's not possible for mIRC to change the whois information, that is controlled by the server, not the client.

I would say theRat is right (or at least his approach is since I haven't tested his code) since the poster also mentioned firewall information which can't appear in whois events from the server.

To my understanding, he was saying he wants /whois to display something like "Watchdog is using a firewall" and I'm saying that can't be done.

I'm afraid they're right. Yes, that's exactly what I was asking for. Thanks for the trick, theRat.