Why is wcf generated proxy getting from object

"Help Update Service" generates partial classes that derive from the object

public partial class Auftrag : object, System.Runtime.Serialization.IExtensibleDataObject

      

        
        
        
      

    

How can I get rid of object inheritance (so I can get another class in the partial class) I don't want to change the auto-generated code.

public partial class Auftrag : System.Runtime.Serialization.IExtensibleDataObject

      

        
        
        
      

    

I want to use the generated proxy classes as data objects inside WPF-ViewModels and so I want to inherit from a custom base class (which also implements IDataErrorInfo). I don't want to copy and paste the implementation for each partial class.