[flexcoders] Changing flex app background color

[whatabrain]

How do I make the background color of my flex app match the color of 
the HTML page behind it? It seems that no matter what I do (short of 
setting background color on mx:Application), I get the default blue-
gray background.

I've tried the following:
1) Using the bgcolor parameter and wmode=transparent when creating the 
   app.
2) Setting backgroundAlpha=0.0 on the mx:Application tag.