[wxGrid] Remove white borders?

Hello

  In "wxPython in Action", I went through the chapter on the Grid
widget, but all the examples display a white border that spills out of
the grid itself:

http://img521.imageshack.us/img521/7577/wxgridlf9.jpg

Is it possible to remove this section? Do I need to play with panels
and sizers?

Thank you.