[Null]

Got this now:

#leftbar {

float: left;

width: 150px;

overflow-x: hidden;

}

#discussions {

margin-left: 170px;

width: 420px;

}

#rightbar {

margin-left: 610px;

width: 150px;

overflow-x: hidden;

}

Total width = 760 px just like the header. This should work, but the right column is still displayed underneeth the discussion div (though the rightbar is aligned to the right and there is enough space left for the rightbar to move up :S