Beta 2 Compiler error - ADO Entities

Hey gang.

I am trying to learn ADO Entities oppose to LINQ to SQL because it supports WCF serializing better than LINQ to SQL does because of circular references which are very common in DB's which the models create.

However the SL2 app when I reference this service that exposes ADO Entities via WCF I get the following error:

Error 1 'System.Runtime.Serialization.DataContractAttribute' does not contain a definition for 'IsReference' ............\Service References\ShopService\Reference.cs

Any ideas? I have installed VS 2k8 SP1 Beta because of the changes in ADO Entities I need to use.

Any help would be greatly appreciated.

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