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First, in Terminal preferences, make sure that the default login shell option is checked, and that "open a saved .term file" is empty/unchecked.

If that looks clean, look for files named .profile and .bash_profile (there could be one or both) in your home directory. Make sure that there isn't an irssi command in either one. (You probably want to remove the offending command, if any, with a text editor, but keep the files around)

Do those places turn up anything?
 
I've got the same problem. I have the file profile in my home directonary.

The only information in there was "test -r /swe/bin/init.sh && . /sw/bin/init.sh, which i tried ereasing with no result.

The checkbox for default login shell in also not filled in.

The problem come after installing irssi with fink.

Irssi app is locaded in /sw/bin/irssi instead of /Application/Utilites/Terminal, like all other apps.

Edit: One solution is connecting to my own computer thru ssh but that feels... a little bit geeky ;-)
 
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