Something

HTML:
<div id="left_left"></div>

---------
CSS:
#left_left {
	background: url('images/left_side.gif');
	background-repeat: repeat-y;
	width: 10px;
	min-height: 100%;
	height: auto !important;
	height: 100%;
	float: left;
	margin: 0px auto;
}