Forum Doublepost prevention isn't working
 

Hello,

I've upgraded to vBulletin 4.2.0 PL2 several hours ago.
I was just trying to test out the new "doublepost prevention" but it seems not to be working.

Here are the settings in Message posting doublepost options:
Time Check Limit = 0
Timestamp Update = Yes
Guest IP Check = Yes
Spacer = Default Spacer
Spacer Color = silver

And this is the setting in Usergroups permission for the usergroup (registered members):
Exclude From Double Post Merges = No

I've tried to log-in as a registered member (not an admin or a moderator) and to tried posting two posts in the same thread, but the posts were not merged.

Any help would be appreciated :)