I Just have had a similar problem to Sebmk
My browser usually saves my correct username and password, but it didn't work.
I then ran out of attempts at which point it asked me for my email... It mentioned some error code when I typed my email...
I then tried the script, it just said "I hope it worked"
Then when I went to login it simple said "login err" not accepting the new login info
My browser then of course auto-filled in the correct old username/password
Not sure what I can do now. Maybe it is a problem with my host, or a bug... My website runs great other then that.
OK>>> UPDATE!
I ran the reset script three times in a row in quick succession and I was able to login with the new username/pass
I think Godaddy was feeling grumpy about running the script or login module....