[Attilitus]

Here is a general solution:

Add this plugin code to init_startup (or any other plugin location occurring before your template is registered.)

PHP Code:

$myarray=array();
$myarray['variable_name']='variable content';
vB_Template::preRegister('template_name', $myarray); 


The result is that {vb:var variable_name} will now take on the value 'variable content' in the template 'template_name'.