resolved - datagrid bound to ibindinglist object

I am having a problem with a datagrid bound to a collection that implements the ibindinglist interface.

I have AllowNew = true so that you can add new rows but the datagrid/currency manager are calling the addnew method (which is part of the ibindinglist interface) twice.

The first time the stack is like this:
DataGrid.OnMouseDown
DataGrid.Set_CurrentCell
DataGrid.AddNewRow
CurrencyManager.AddNew
myCollection.AddNew

The second time there is a couple of other calls in the stack:
DataGrid.OnMouseDown
DataGrid.Set_CurrentCell
DataGridAddNewRow.onEdit
DataGird.Edit
DataGrid.Edit
DataGrid.AddNewRow
CurrencyManager.AddNew
myCollection.AddNew

I have looked all through the code and breakpointed like crazy - it doesn't seem to be my code that is the problem.

Any ideas?