a wxpython question about frames and panels

[sameer]

I have a panel within a frame.  I use sizers to layout items in the
panel.  The frame is nothing but a container for the panel and a menu
bar and does not use any sizers.  When I start the script, the Panel
takes up the smallest amount of space possible, and much of the frame
is left gray and unused.  When I resize the frame by shrinking it or
expanding it by pulling on the frame border, the Panel suddently takes
up all the space in the frame, like it should do initially, but
doesn't.  How can I fix this so on initialization, the panel takes up
all the space provided by the frame?

BTW, I am on a win2k system, running python 2.1, and wxpython 2.3.