commenter anonymous, dispite filling in comment fields

i recently upgraded from 1.2, and ever since, i’ve had all sorts of problems with people unable to leave comments. First of all, they weren’t able to leave them at all, but through dumb luck i managed to fix that.

Now the problem is that even when they fill out the Name, Email etc fields, it still says “posted by anonymous” when they leave the comment. The frustrating thing, is that when I leave a comment, it recognises my details, just not anyone elses.

What am I doing wrong?

here’s what I mean:
https://angrylittleman.org/index.php/2005/06/28/comment-engage/