[MarkFL]

You would want to use the PHP Plugin Hook "postbit_display_complete" and then your code would be like:

PHP Code:

if (THIS_SCRIPT === 'usernote' AND is_member_of($vbulletin->userinfo, array(X, Y, Z, ...)))
{
    $post['message'] .= '<br /><br />This is just an additional message';
} 


where "X, Y, Z, ..." are the usergroupids of the usergroups you want to see the additional message.