HTML Table Center of Page

Hi,

I have a HTML table with height & width same (400 px  x  400 px) and I place a picture as background of this table. I want 100% centralize this table as Horizontally also in vertically in all screen resolution and in all browsers. I can centralize it horizontally but fail to vertically. If I set it centrally for IE 6.0 then it not remain in centre in IE 7.0 or FF.

Can anyone give me some client side or server side script for resolve this problem.

I am using VS 2005.

Thanks in advance.
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