(1) method drawCell() - correct clipping set, when drawing spanned cells, which is partially scrolled away (in order to not overwrite header cells, which are on top of the spanned-scrolled cells)
(2) method onMouseDown() - correct click processing on spanned cells - clicking inside the spanned cell (and not the top left 'cell' of the span) was not handled correctly
Generated from out svn copy, but the change is quite clear