Related Items RelationSpec xml for Virtual Machine typ

I wish to add a Related Items tab for Virtual Machines associated with our plugin systems.   I looked at the Chassis Rack samples to figure out how to add support for HostSystem and Datastore type objects, but my plugin xml does not work (add Related Items tab) when I modified it for Virtual Machines.  


Can someone recommend the RelationSpec xml required for Virtual Machine object types?  I looked for documentation, but it just refers me back to the Chassis sample, which does not provide info for Virtual Machines.   By the way, I updated my relevant DataAdapter class to add a type, VirtualMachine, and supported relations, including forward and reverse relations.


Here is some sample xml that does +not +work.


            <com.vmware.ui.relateditems.model.RelationSpec>

               <id>virtualmachineForMySystem</id>

               <icon>#</icon>

               <label>#</label>

               <relation>virtualmachine</relation>

               <targetType>VirtualMachine</targetType>

               <listViewId>vsphere.core.virtualmachine.list</listViewId>

            </com.vmware.ui.relateditems.model.RelationSpec>