IE 6.0 does not support 32-bit transparent PNG correctly. It displays the alpha channel (transparency) as a simple gray background. (Palette PNGs with transparency in IE6 are good.) Most other browsers work correctly, though, including IE 7.0+, Firefox, Safari, Chrome, Netscape, Opera, Epiphany, Konqueror ...
The easiest solution for IE 6.0 transparency is to use GIFs. If this is not possible, JavaScript and CSS are available on 24ways .
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