Unable to get QuickStats for vApp’s virtual machine through VCO workflow

Hi,

I have written a workflow to retrieve QuickStats for virtual machines it works fine for all plain vCenter virtual machines but it won't for virtual machine’s those belongs to vClould Directors vApp(virtual Appliance). Script for my workflow is herein

for (var i in vcVms) {

    var vm = vcVms[i];

System.log("Virtual Machine Name"+virtualMc.name);
System.log("balloonedMemory "+virtualMc.summary.quickStats.balloonedMemory);
System.log("compressedMemory "+virtualMc.summary.quickStats.compressedMemory);
System.log("consumedOverheadMemory "+virtualMc.summary.quickStats.consumedOverheadMemory);
System.log("distributedCpuEntitlement "+virtualMc.summary.quickStats.distributedCpuEntitlement);
......
.....
System.log("ssdSwappedMemory "+virtualMc.summary.quickStats.ssdSwappedMemory);
System.log("staticMemoryEntitlement"+virtualMc.summary.quickStats.staticMemoryEntitlement);
System.log("swappedMemory "+virtualMc.summary.quickStats.swappedMemory);
System.log("uptimeSeconds "+virtualMc.summary.quickStats.uptimeSeconds);

}

Please correct me where I am wrong or whats iccorect in my workflow. Is there any limitation  of the api?

--AVR