nswindow alphaComponent and shadow images

FROM : Cornelius Jaeger
DATE : Thu Apr 21 10:48:46 2005

hi all,

i have a problem with getting rid of shadow images on a near
transparent window.
basically it's a slideshow and you can set the slide shows window to
have an alpha value less than 1.0
when i set the alpha value the first picture that was shown in the
window can still be seen albeit very faintly.
how can i get rid of this?

thx

cornelius