Have you enabled HTML in the vBulletin CMS Permissions section? Its pretty simple, almost as simple as cut and paste, once its enabled.
It gets more complicated when you want html enabled in replies, comments, blogs etc. as there are multiple areas where you would need to enable html, and it could pose hack risks.
--------------- Added [DATE]1287905862[/DATE] at [TIME]1287905862[/TIME] ---------------
If your just looking to add links, you may want to try an add-on to manage links.
Below is a cool add-on for link management:
https://vborg.vbsupport.ru/showthrea...highlight=link