Hi, thanks for your contribute.
Here are some possibilities
1. Conflict with Register-Plus : have you simultaneously activated both of them ?
2. Conflict with other plugins : Have you tried activating Dregister as the only plugin of your blog, just to see if it works ?
3. Corrupt installation : have you tried on a clean WP installation ?
Let me know you results !
Seems to be a plugin-related problem. Try de-activating yours.
Having the same problem here.
It’s not theme-related for what I can see from now.
I’ll try various re-installations and get back to you..