Riyatch, you have to make a few file modifications, one to ./admincp/index.php and one to ./includes/adminfunctions_navpanel.php
Then, you have to refresh your navpanel for it to start showing up
Cyo: look at the first post in this thread, there's a big link:
Tutorial
How to upgrade your vBulletin using the Hack Tracking Log
That'll guide you through the upgrade process in only 4 simple steps