Get/Set/New-AdvancedSetting ESXi

I am getting "Current license or ESXi version prohibits execurtion of the requested operation" running the following command from a remote powershell client.

PS C:\Windows> get-advancedsetting -entity (get-vm SERVER) -name 'Devices.Hotplug' | Set-AdvancedSetting -value 'true'
Set-AdvancedSetting : 3/21/2013 3:10:02 PM    Set-AdvancedSetting        Current license or ESXi version prohibits
execution of the requested operation.   
At line:1 char:79
+ get-advancedsetting -entity (get-vm iowavmaod40tst) -name 'Devices.Hotplug' | Se ...
+                                                                               ~~
    + CategoryInfo          : NotSpecified: (:) [Set-AdvancedSetting], RestrictedVersion
    + FullyQualifiedErrorId : Client20_SystemManagementServiceImpl_UpdateVMAdvancedOption_VIError,VMware.VimAutomation.ViCo
   re.Cmdlets.Commands.SetAdvancedSetting

Shouldn't PS C:\Windows> get-advancedsetting -entity (get-vm iowavmaod40tst) -name 'Devices.Hotplug' | Set-AdvancedSetting -value 'true'
Set-AdvancedSetting : 3/21/2013 3:10:02 PM    Set-AdvancedSetting        Current license or ESXi version prohibits
execution of the requested operation.   
At line:1 char:79
+ get-advancedsetting -entity (get-vm iowavmaod40tst) -name 'Devices.Hotplug' | Se ...
+                                                                               ~~
    + CategoryInfo          : NotSpecified: (:) [Set-AdvancedSetting], RestrictedVersion
    + FullyQualifiedErrorId : Client20_SystemManagementServiceImpl_UpdateVMAdvancedOption_VIError,VMware.VimAutomation.ViCo
   re.Cmdlets.Commands.SetAdvancedSetting

I was under the impression this could be done with ESXi?  Am I mistaken?

Thanks