samuelmpmac said:

 I have almost the same problem, but i also have to allow the user to add the row (add new row) when pressing the enter key in the last editable cell or when the focus is on the last cell, but the last column is not editable (it's value is set programatically using javascript). Anyone have any idea of how can i do that? I tried some javascript similar to the one posted before, but it didn't work, because i could'nt find any method to tell the grid that i want this add new row to be added (client side). Also it captures the "enter" even if the cell is not in edit mode (only active), so the enter doesn't work to get the cell editable, the routine is executed and everything gets messed up... 

I found this in the CSOM for the Uwg:

AddNewRow

The add new row object. Inherited from the row object. All properties and methods from the row object are applicable to the add new row object. Plus there are several new ones.

With the help of mleevisiphor and Chandradeep from the support i came to a solution that solved my problem. Here's the code i used:

        function KeyDown(gridName, cellId, key)
        {
                var grid = igtbl_getGridById(gridName);
                var cell = igtbl_getCellById(cellId);

                if((cell.Index == (grid.Bands[0].Columns.length - 1)) && key == 13)
                      var aNovaRow = cell.getRow().commit();
                      aNovaRow = aNovaRow.getNextRow(true);
                      var aNovaCelula = aNovaRow.getCell(0);
                      aNovaCelula.activate();

        }

Thank you all for the help! 

But don't forget about mine =)