TrafficManager external endpoint that belongs to another subscription

Hey There,

My website is hosted on multiple locations across 2 subscriptions. I'm not trying to configure TrafficManager to which is hosted by Subscription A to point to an endpoint thats hosted on Subscription B using powershell however I get the following error:

PS C:\Windows\system32> Set-AzureTrafficManagerProfile $profileSet-AzureTrafficManagerProfile : BadRequest: Some of the provided Azure Website endpoints are not valid: Traffic manager configuration is not valid because one or more domains do not belong to subscription "xxx": xxx.azurewebsites.net
At line:1 char:1+ Set-AzureTrafficManagerProfile $profile+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~    + CategoryInfo          : CloseError: (:) [Set-AzureTrafficManagerProfile], CloudException    + FullyQualifiedErrorId : Microsoft.WindowsAzure.Commands.TrafficManager.Profile.SetAzureTrafficManagerProfile 

So does that mean external endpoints are only allowed as long as they are not hosted on Azure? that would really be a pain....

Thanks!