I found out that if I have the two same mirc.exe running with the following configuration:
#1: connected to servers
#2: not connected to any server + remote off
Both of them have the 'show identd requests' option set.
And if I get #1 to disconnect and reconnect on a lot of connections at the same time (also happens with the on start event if I'm using some /server -m command, but it doesn't happen if I just connect to one server for example)
I get the Identd request in #2, and the IP matches the ones from where #1 is connecting to.
I doubt it's a problem with mIRC but it can't really be anything else imo
I have it on video (#1 is on the left) here
It's not clear on the video, but of course, if I check the status windows on #1, they do not have the appropriate Identd requests.