<link href="css/bootstrap.css" rel="stylesheet">
<link href="css/datepicker.css" rel="stylesheet">
<script src="js/bootstrap-datepicker.js"></script>
<script type="text/javascript" src="js/bootstrap.js"></script>
<script type="text/javascript" src="js/jquery-1.8.0.js"></script>

<div class="controls">
        <input data-datepicker="datepicker" class="span3" value="2012-09-13" data-date-format="yyyy-mm-dd" id="dp2" >
        </div>

$('#dp2').datepicker();

.datepicker {
z-index: 9999;
top: 0;
left: 0;
padding: 4px;
margin-top: 1px;
-webkit-border-radius: 4px;
-moz-border-radius: 4px;
border-radius: 4px;
}