var name = "#subAreaInner";
var menuYloc = null;
$(document).ready(function(){
var $w = $( window ),$html = $( 'html' ),$right = $( '#mainArea' ),$left = $( '#subAreaInner' );
menuYloc = $left.offset().top;
$w.scroll(function () {
var menunHeight = $left.height(),
contHeight = $right.height(),
menuTop = menuYloc,
scrollTop = $w.scrollTop(),
columnTopHeibht = menuTop - scrollTop,
columnUnderHeibht = $w.scrollTop() + menunHeight - menuYloc;
//alert(columnTop);

if (columnTopHeibht < 0 && contHeight > columnUnderHeibht) {
	offset = -menuYloc+$(document).scrollTop()+"px";
	$(name).css({top:offset},{duration:500,queue:false});
};
});
});