I no longer use mirc, however, it used to support ip/port arguments in the command. In other terms, DCC chat used to handle connections similar to telnet.
Mirc doesn`t really support telnet. It supports dcc chats. I could input
/dcc chat ip port
Mirc will send 100 clientnickname (100 myircnickname)
The eggdrop will show a errormessage:
Refused telnet@myhost (invalid handle: 100 ircnickname)
It works nearly. Perhaps i should ask for it in the mirc forums. With some minor changes this could be possible.