datagridview combobox binding

Hi,
I have a datagridview that is databound to a BindingSource containing objects of type MyCustomClass.

MyCustomClass contains two Properties (Name, Class) and 1 dictionary, myUserDictionary<string,string>

class MyCustomClass{

string Name {get;set;}
string Class {get;set;}
Dictionary<string,string> myUserDictionary;

}

Is there a way to set a DataGridViewComboBoxColumn's DataPropertyName attribute to a specific <key,value> pair of myUserDictionary?

This one has me stumped...

the time it will take you to figure out , you'll wish you'd simply used a strongly typed datatable. it has all the features you seek if you make one column the primary key