So it is impossible. Not often you hear that.

Tom - I wanted it to work exactly as Conditional Formatting (on the active
cell), apart from controlling the ColorIndex from A1...or any other cell.
(Example: =ColorCell(C43)).
Bob - It's a good add-in, but since I'm going to send this spreadsheet to a
number of people around Europe, I can't ask them to download and install an
add-in. That's why a small VBA code had been perfect.

Thanks anyway, I appreciate the effort.
Ola

FWIW, good article: http://www.developerfusion.com/show/35/7/