as to continue this mod on vbulletin version 5 , here it is!
What this hack do ?
when a private message is received or a visitor message or a friend request or a social group invitation a cute and kind post man comes to the screen and informs the user , with a link to vbulletin's notification center.
Installation Guide :
1-upload the "upload" folder (images) to appropriate folde: your_forum/images/misc/
2-go to admin cp => Products & Hooks => Manage Products => [Add/Import Product] => choose the XML file from your computer and hit "Import"
it's now installed , just go to : Settings => Options => PostMan Notification
you have control over images , on/off hack / on/off author's copyright and an option to limit the hack only to forum's main page
additionally you can turn this hack ON/OFF and disable copyright (not recommended) in vbulletin options page.