I have a wrapper div which contans 2 divs next to each other. Above this container I have a div that contains my header. The wrapper div must be 100% minus the height of the
Here is a working css, tested under Firefox / IE7 / Safari / Chrome / Opera.
* {margin:0px;padding:0px;overflow:hidden}
div {position:absolute}
div#header {top:0px;left:0px;right:0px;height:60px}
div#wrapper {top:60px;left:0px;right:0px;bottom:0px;}
div#left {top:0px;bottom:0px;left:0px;width:50%;overflow-y:auto}
div#right {top:0px;bottom:0px;right:0px;width:50%;overflow-y:auto}
"overflow-y" is not w3c-approved, but every major browser supports it. Your two divs #left and #right will display a vertical scrollbar if their content is too high.
For this to work under IE7, you have to trigger the standards-compliant mode by adding a DOCTYPE :
high content