How do I disable the profile links when clicking on a person's name?

We've set up a housing forum with guest posting and I've been able to turn off most of the extras, but I can't seem to kill the active links that are on a name once someone has posted. If you click their name, it takes you to a login screen. I just want the names to be non-link text. Is there a way to do this? I don't mind hacking some template files if I have to.

thanks!