Transparent Bitmap and StringGrid Problem

Hi

I have a bitmap of a double headed arrow on an clOlive background, which I
draw onto a cell in a stringGrid (Column 2). The color of the arrow changes
depending on the value of the under lying cell. However the text decription,
which is in the cell before (Column 1), does not display if the
bitmap transparent property is set to True.  The first entry displays and if
I click on an other text cell
it appears but not when the cell is first drawn, It does not matter how the
text is
drawn ie. TextRect, TextOut or Default drawing.
Any ideas please.

Thanks
Alan