AddNew and Databinding

I have a simple form with one textbox bound to a datatable. A button is provided to allow the user in input new data. I am having problem with the databinding when adding a new record.

If I try...

dim rw as datarow = MyTable.NewRow()
MyTable.Rows.Add(rw)

I can see the row has been adding but I cannot get my currencymanager to point to the new row.

If I try...
cm.AddNew() 'cm = currency manager

The textbox clears (cm added a new row) but when I endcurrentedit a new row is not added to the datatable.

Any Ideas ...