Copy Scale on Empty with negatve value does not work.

I want to flip an object by changing its constraint Copy Scale`s target from one Empty to another Empty with an negative X value, but when it arrive at the new Empty its still facing the same direction. If I do it with a cube instead of the Empty it works, just not with the Empty. Is it possible to get it working with the Empty? Or is it some how not possible to copy a negative scaling from an Empty. Thx in advance…Spero…