[DataGrid] System.IndexOutOfRangeException: list position

Hi,

I have a simple DataGrid in which I load data from a DataSet.
Data loading works fine but when I try to add a row I get a MessageBox that tells me to correct the value.
Then I get this error: System.IndexOutOfRangeException: list position.

Can anyone help me?

Thanks, Michele

Mono 1.9.1 / Suse 10.3