XMLRPC result is empty or NULL gives drupal error

Hi,

When i'm using an xmlrpc call, and this call doesn't find any matching results, it returns NULL making it look like:

<?xml version="1.0" encoding="UTF-8"?>

However this creates an error in Drupal:

Notice: Undefined property: stdClass::$params in _xmlrpc() (line 596 of C:\local_projects\Essentv2\includes\xmlrpc.inc).

Because it expects to have a $message->params[0], but it doesn't because it ignores the NULL result.

What must i do to fix this?
I can easly write a check if $message->params[0] exists and return NULL again instead, but I'm not sure if I am returning a wrong result or the Drupal core function is ok.
Since i can't find anything saying returning an empty result is bad, since you can always have an empty result right..