Generic set of WCF problem passing

Question

I have a generic collection

[KnownType(typeof(Brand))]
[CollectionDataContract]
[Serializable]
public class PageOfItems<T> : List<T>
{
public PageOfItems()
{ }

}

Call is

[OperationContract]
[ServiceKnownType(typeof(Brand))]
PageOfItems<Brand> GetBrands(PagingInfo pagingInfo);

In reference to the service client, the returned object is the

JShop.PageOfItemsOfBrand7rzGfijk

The right should be

JShop.PageOfItems

How does this solution?