How to edit GridViewCell?

[Matan]

 Have a RadGridView with a RadContextMenu whice contains a RadMenuItem.
Clicking on that RadMenuItem should allow the user to edit the relavent GridViewCell.
In reallity the cell becomes ediable but doesn't accept any key strokes except Backspace, Enter and Esc.
How may I fix that?

Thanks!

[Matan]

OK having 
    Keyboard.Focus(radGridView);
    radGridView.Focus(); 
in 
    radGridView_PreparedCellForEdit

had fixed the problem