Saving a figure to a file without losing the background color.

Hi,

I'm having trouble saving a figure with Matlab. Everytime I do, I lose the background color in the windows bitmap file I get. I create a figure and give it a black background using:
set(gcf,'Color','k');

Then I save it to a windows bitmap using
saveas(gcf, 'figurename', 'bmp');

Everytime I do that though, the background in the bitmap file changes to white! :'(
Is there any way to save the file without losing the black background? I'm using Matlab V7 and for my project I have to save the file as a .bmp .

Thank-you! :)
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