ManagedObjectReference subclasses missing in C# generated code

I see tons of references to VirtualMachine, HostSystem, DataCenter classes (among many others) in the API Reference but they were never generated in the proxy code.  I checked the wsdl's and xsd's for vim and vim25 and found no reference to those classes.  I also checked the Java samples and there is no reference to them in there either.

I'm trying a simple example call to FindByIp to get a VirtualMachine object back.  I turned on System.Net debugging to see if the SOAP response was sending back more information than just the type and Value in the ManagedObjectReference class and it's not.

Any ideas as to why these classes are missing from the API even though they are referenced throughout the API refrence docs?

THanks,
Dan