new PersistenceSpecification<Component>(session, new ComponentEqualityComparer())
 
public class ComponentEqualityComparer : IEqualityComparer
{
    #region IEqualityComparer Members
 
    public bool Equals(object x, object y)
    {
        if (x == null || y == null)
        {
            return false;
        }
 
        if (x is DateTime && y is DateTime)
        {
            return true;
        }
 
        if (x is ComponentInstance && y is ComponentInstance)
        {
            return ((ComponentInstance)x).SubscriptionId == ((ComponentInstance)y).SubscriptionId;
        }
 
        return x.Equals(y);
    }
 
    public int GetHashCode(object obj)
    {
        throw new NotImplementedException();
    }
 
    #endregion
}