Originally posted here by MsMittens
It's not a bug. That's how the bump up feature works. What we do need, however, is a "Who bumped da thread" feature.
If they do do something like this, let me just point out that the bump up feature relies on a link basically that uses your userid when you bump it up. After seeing this I decided to test using someone elses userid on a thread that was already close to the top so noone would really notice or mind. When I did this, it gave me no errors, so this must be fixed if a bumpup is going to be associated with a user, otherwise there will be bumpup spoofing.