I have two DIVs with absolute position on two sides of a HTML page such as (EXAMPLE)
so far (2012) It's not possible using CSS, CSS3 (with 2 separate elements)
but using JS You can clone the content and use scrollTop on the right element :
LIVE DEMO
var d = document,
$left = d.getElementById('left'),
$right = d.getElementById('right'),
leftH = $left.offsetHeight;
$right.innerHTML = $left.innerHTML +'';
$right.scrollTop = leftH;
As you can see I'm appending also an empty paragraph, to fix the right element need to scrollTop some amount of px
Note: add overflow:hidden; to your ID elements #left and #right