I want to add a bool variable and property to the base Entity class in my RIA services project so that it is available throughout all the entity objects but seem unable to work out how to do this. I know that adding properties to actual entities themselves is easy using .shared.cs and partial classes but adding such properties to the Entity class using similar methods doesn't work.

For example, the following code doesn't work

namespace System.ServiceModel.DomainServices.Client
{
    public abstract partial class Entity
    {
        private bool auditRequired;
        public bool AuditRequired
        {
            get { return auditRequired; }
            set { auditRequired = value; }
        }
    }
}

All that happens is that the existing Entity class gets totally overriden rather than extending the Entity class.

How do I extend the base Entity class so that functionality is available thoughout all derived entity classes?