dotnet windows forms databinding: Hi,

I have a very simple situation.

I have class with a property that returns an Interface type.
For example:

class Person
{

public IPersonName Name
{
get{return name;}
}

public PersonName RealName
{
get {return name as PersonName;}
}
}

The IPersonName is an interface.
This is just for testing purposes.
Elements of this class are shown in a DataGrid with 2 columns.
The RealName shows properly but the Name column that should have the
same value remains blank!.
I only added the interface.. the PersonName overrides ToString
correctly. I think i'm missing something.. don't know what.
Could you help me a little?