You can create you own function by making a switch statement.
For example:
PHP Code:
function user_class_color($class, $username) {
switch ($class)
{
case VIP:
return "<span style='color: red;'>" . $username . "</span>";
break;
case USER:
return "<span style='color: blue;'>" . $username . "</span>";
break;
}
return "$username";
}