Userid displaying in member.php

[BeatificFaith]

Hi,
I'm writing a script where I would like to display information on the member.php page based on the userid. This works great when I call the member.php page from a post, but if I click on the name on forumhome, the userid doesn't get sent as it's based on lastposter. What can I do to fix this?

This is the SQL:

PHP Code:

SELECT field5
FROM userfield
WHERE userid=".$vbulletin->GPC['userid'] 

This is just for testing purposes, I know there are better ways to display field5 on the member page .