When a new member signs up and you have Welcome Private Message set in vBulletin it used to show in shout that user has a pm, but I don't see that happening anymore.
Well I spoke too soon, if you add a user in acp it shows the pm message in shout, but if a user signs up to the forum, it don't show the pm message, and I know the forum pm was sent, I verified it in phpmyadmin.
Before I test this, could you please re-download and re-upload the files? Your forum appears to be affected by a bug I fixed a few hours ago but couldn't explain why I couldn't reproduce.
Your shoutbox doesn't refresh on inserting a new shout / editing a shout / deleting a shout, only after a minute.
Does your "Welcome PM User" have permission to shout? As in, is the person whose username you have added part of a usergroup that has permissions to shout in the shoutbox?
Another hotfix. I didn't take into consideration that the permissions I used to check would be from the visiting user, not the user who actually submitted the shout.
I also added support for "automated shouts" - notification-based shouts will in the future ignore many permission checks (they ARE automated, after all) which should prevent this from happening again