[Typo3] PNG-24 & CSS not working with the tpg_iepngfix extension

[dieter orens]

hey, I have a little problem with png24 images.
I have installed the extension which resolves the problem of the gray 
background in
IE, and this works fine.
But when I use these kinds of pictures through  external CSS, this extension 
doesn't seem to work.
Can this be configured somewhere or is there another solution?

grtz,