Run mIRC, then type: /help on TEXT
This will bring up the appropriate mIRC help page, scroll to the bottom of the help and read the Note.
Now, go back to mIRC, then type: /help on INPUT
This will bring up the appropriate mIRC help page which you require to do what you want to do.
Basically I think it comes to a matter of copy/pasting the on TEXT stuff and changing it to on INPUT so that it also works for yourself, but you'll have to see for yourself.
Hope this is useful to you, good luck.
