Ok that was helpful. I've been looking for the msdn of vbulletin, but I have another question...
If I put some html in a php variable (like $myvar = "<TABLE> STUFF </TABLE>

, then ask it to show on a custom template, it still strips out the chars. Do I need to put a function of some sort on the template itself to allow it to be treated as code and not < $gt chars?
Here is a pseudo of what i'm doing...
PLUGIN in global_start:
PHP Code:
$myvar = "<table> Stuff </table>";
eval $myvar on custom_template;
CUSTOM_TEMPLATE
EDIT: Can I use
(taken from the api)
string unhtmlspecialchars (string $text, [boolean $doUniCode = false])
in a template?