ManagedObjectReference is not the object itself.
Its just the "reference" to the objects that sits on the server side. So it has two properties only: type and Value.
To get the properties of the \*real* object you need to use some property collecting tool. There's property collector to do that, but it's a bit of a pain to use it (don't know about Perl, but in C# it definitely is!).
What you have to do is to create the PropertyFilterSpec object and set it's objectSet property to the array of ManagedObjectReferences to the objects you want to get properties of.
Next you need to prepare the PropertySpec object(s) to tell which propertis you want and set the propertySpec field of PropertyFilterSpec.
Then you put it all together and call something like:
vim_service.RetrieveProperties(service_content.propertyCollector, property_filter_spec)
and with a little bit of luck you should get what you need.
