Div Height

I have a simple div defined as follows:

#leftbar {
position: absolute;
top: 0px;
left: 0;
margin: 0;
border: 0px dashed #999;
width: 100px;
height:100%;
background: #CCCCFF;

}

and also in the css I have

body,html {
height:100%;
min-height:100%;
}

But the column does not fill the page as it should and cuts off after a
certain point, in both firefox and IE. Any ideas how to remedy this ? I
know it CAN be done but I'm stuck.