When I do a whois to certain people, I sometimes get a reply like "Why did you whois me? You are person number # to whois me" (# is the actual number)

How do they do that?

It all depends on where the message occurs. If the message is next to their address then it means little because that is just the "Full Name" setting in a chat programme. Some chatters just put that there it make the 'whoisers' out there wonder about it all.

If the message was in a private or notice reply then the user you whois'd is likely to be an oper as they are the only ones that can tell when you do a whois on them. They get the message via a server notice and could script an automated reply via that.

You can do the same thing by editing your IDENT in Mirc Options\connect\ident

With only 10 characters to play with? Better off editing Full Name setting. Though, of course, that will not actually count the number of whoises you get. Only an oper would be able to have that privilege.

I think it's just because they are an op in their channel and their clone is an ircop

Hmmm, an unlikely scenario, but certainly possible. I usually oper myself and have second connection unopered.

most likely u are whoising ppl who are ircops ... they can see your whois of them ... thats an added thing in there so that ircops can kinda know when someone neds help

Was that responce really neccesary d3m0n? The idea was already mentioned..

yes and i can see your response is just as helpful