Conditional formatting from one sheet to another

[seasteel]

I would like to use conditional formatting between 2 different sheets in
the same workbook.

I.e I have one sheet that should only present different colours in the
cells using conditional formatting. The base for this is calculations
done in another sheet.

Example

Cell A1 in sheet TEST1 should be red IF the value in cell A1 in sheet
TEST2 = 5

I have no problem using conditional formatting generally speaking but
Excel 2007 do not allow me to use references to other worksheets for
conditional formatting criterias.

Is there a work around for this?

Kind Regards

Seasteel