InvalidPropertyFaultMsg collecting property portWorldWideName in FibreChannelHba

ManagedObjectReference hsdi = new ManagedObjectReference();  hsdi.setType("HostSystem");  hsdi.setValue("host-28");  ObjectSpec objectSpec = new ObjectSpec();  objectSpec.setObj(hsdi);
PropertySpec propertySpec = new PropertySpec();  propertySpec.setType("HostSystem");  propertySpec    .getPathSet()    .add(      "config.storageDevice.hostBusAdapter[\"key-vim.host.FibreChannelHba-vmhba1\"].portWorldWideName");

I want to read all WWPNs from a host. The code above cause an error. Any ideas why the property doesn't exist.

The MOB shows the property.

If I read the storageDeviceInfo and call getHostBusAdapter() all elements in the list are type of HostHostBusAdapter, so it's not possible to call the getter for WWPN's.

Why did I get the wrong class type from the server? Casting cause an error.