How can I get the left div to stretch to the height of the right div, even though it has less content?

Thanks

HTML Code:
<style>
.left{width:50px;float:left;background:#0099ff;position:absolute;}
.right{position:absolute;width:50px;float:right;background:#007774;height:auto;position:relative;display:block;}
.container{width:100px;background:#000000;overflow:hidden;display:inline-block;}
</style>

<div class="container">
<div class="left">
testing<br />
testing<br />
</div>


<div class="right">
testing<br />
testing<br />
testing<br />
testing<br />
</div>

</div>