Sizers / Windows

I just tried my latest wxPython app on Windows 2000 (I've been doing the
development under Ubuntu). I know that for Windows you need to add a
Panel to the Frame to show the background in the normal window
background color. I've done that, but to add nice borders around on the
frame, when I added the panel to the main sizer, I gave it a 5 pixel
border all the way around. This border area is displaying in a
different color. I assume that it is the same color that the whole
window background would use if there were no main panel.

Is there an easy way around this, or do I need to go back and remove the
border from the top sizer and move it to sizers within the panel?