Excuse me if this has been reported already, but it seems to me that /server has a bug.
The mIRC helpfile states that -n behaves the same as -m, except that it will not connect to the server. However, when I use -n instead of -m in a /server command that also includes -i settings, mIRC will suddenly not use the settings from the -i parameter anymore, and use the identity settings of the "main" server instead.
Yes, I'm aware of the possible workarounds, but still...