[kh99]

The code you posted is both rendering the postbit_legacy template and preRegistering your variable to it. You don't need to do both. I think you probably just need the preRegister part, like:

$new_buddylist = explode(' ', $bbuserinfo['buddylist']);
$templatevalues['my_buddylist'] = $new_buddylist; 
vB_Template::preRegister('postbit_legacy', $templatevalues);

Then you'd use $my_buddylist in template postbit_legacy.