VIServer registered vm's method won't work with resource_pool filter

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Instantiate a VIServer object and connect to vcenter server;
2. Try to get registered VM's using a resource pool as a filter;

What is the expected output? What do you see instead?
The list of vm's inside the resource pool.

What version of the product are you using? On what operating system?
Vmware Vcenter 5.0.

Client libs:

Ubuntu 12.10
Python 2.7
pysphere==0.1.7

Original issue reported on code.google.com by [email protected] on 5 Dec 2012 at 6:07