I did a Google search for Minitel. If sounds like that's a terminal for an online service that was offered through some telephone companies. It used a different protocol for the modem (hardware level is v.23) and it used a different protocol at the software level (X.25). So I'm guessing that the chances of your using it as a terminal for your Linux box is about nil. But if you do get it working, at least there's a termcap entry for it.

(NOTE: I'm making a lot of assumptions here. It's generally useful if people list the make and model of something as well as what ports appear to be available.)