CSS: Efficient Centering of DIV content

[font=System][size=2]Hello,

I’m interested in some feedback and suggestions on centering both horizontally and vertically DIV content on the following page.

www.demo.zanzinato.com/center

I am trying to move away from a tables based layout and would like this to be as clean and optimized as possible. I am aiming for fixed horizontal width but fluid vertical height. I’ve got a pretty good start however I would like to get it working in Mac IE 5.2.3 and it seems to be having trouble with one of the backgrounds.

If you could glance this over I would be most interested in other opinions.

Thanks a lot!
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