Problem with update in datagrid bound to datatable

Hi, I have a very weird problem I can´t find how to solve. I have a dataGrid bound to a dataTable. When I add a new row to the dataTable with the Rows.InsertAt method (meaning I don´t add it at the end, but in order), the dataGrid shows the new row BUT NOT AT ITS INSERT POSITION, but at the end of the table. How can I make the dataGrid update exactly what is on the dataTable, with the same order? Thanks very much in advance because I have tried many things (Refresh, Update, ...) and none have worked! Cheers, Juanjo