I have an annoying problem that causes my css boxes to overflow in IE.
You can see the problem here

The CSS for these boxes is as follows
.rbroundbox { background: url(images/postbackground.gif) repeat; }
.rbtop div  { background: url(images/topleft.gif) no-repeat top left; }
.rbtop      { background: url(images/topright.gif) no-repeat top right; }
.rbbot div  { background: url(images/bottomleft.gif) no-repeat bottom left; }
.rbbot      { background: url(images/bottomright.gif) no-repeat bottom right; }

 /* height and width stuff, width not really nessisary. */
.rbtop div, .rbtop, .rbbot div, .rbbot {
	width: 100%;
	height: 7px;
	font-size: 1px;
.rbcontent  { margin: 0 7px; }
.rbroundbox { width: 60%; margin: 1em auto; }
The HTML is
<div class="rbroundbox">
<div class="rbtop"><div></div></div>
<div class="rbcontent">

<table border="0" width="100%" cellspacing="0" cellpadding="0">
    <td width="100%">

<p><font face="Tahoma" size="2">Posted by <a href="mailto:[INSERT EMAIL]">[INSERT REALNAME]</a> at [INSERT DATE]</font></p>
</div><!-- /rbcontent -->
<div class="rbbot"><div></div></div>
</div><!-- /rbroundbox -->
What is causing the overflow in IE? it doesnt show up in any other browser I know of.