Cause remains unknown, but here's a workaround

I'm using attached_node to include a bunch of teasers in another node. In Firefox and Safari, everything is peachy. But when I test the page in IE6 on XP, the attached nodes are all displayed with a gray background, surrounded by irregular dashed-line borders. Very, very, very UGLY.

I've tried everything I know how to do to control this. I can't make it stop. I've even tried hacking the module to change the class names for the div containers, and it doesn't seem to do any good.

The behavior would be quite interesting, if I didn't have to get this in front of a client very soon. What's happening is clearly that IE thinks some container is unclosed. If you'll look at the attached screenshot, you'll be able to see that the ugliness is iteratively enhanced: The dates in the attached screenshot are headings, and the blue subheadings is an attached node. You can see that the first attached node is unaffected, but the subsequent containers up to the close of the #content container are progressively more munged.

I've tried removing the headers, on the notion that they might be to blame. No dice.

Here's a snip of the page source that produces this mess -- as you can see, I've taken some basic steps to try to isolate the problem by changing the names of the sub-containers to eliminate CSS nesting issues as much as I feasibly can:

<h4 class="pr-month">May 2006</h4>
<div class="attached_node"><div class="att-node">
		<h2><a href="/pr/2006-May-Ground-Rules-Are-Changing" title="The Ground Rules Are Changing">The Ground Rules Are Changing</a></h2>
		<div class="att-content">
		<p>… New book offers a formula for thriving in the new outsourced economy. Thousands of jobs are moving to countries every month where they can be done as well for less money. We can’t stop it from happening. But we can change the way we adapt to this new reality and how we engage with it.  <a href="/pr/2006-May-Ground-Rules-Are-Changing">Read more</a>.</p> 	</div>

		<div class="metacontent">
		<div class="links"><strong>Links:</strong> <span class="metacontent list"><ul class="metacontent list"><li><a href="/pr/2006-May-Ground-Rules-Are-Changing" title="Read the rest of this posting." class="read-more">read more</a></li></ul> </span></div>					</div>
	</div>
</div>


<h4 class="pr-month">September 2006</h4>

<div class="attached_node"><div class="att-node">
		<h2><a href="/pr/2006-Sep-About-Mike-Cook" title="About Mike Cook">About Mike Cook</a></h2>
		<div class="att-content">
		<p>… a nationally recognized expert in leadership and workforce development and the author of <em>THRIVE: Standing on Your Own Two Feet in a Borderless World</em>. <a href="/pr/2006-Sep-About-Mike-Cook">Read more</a>. </p>
	</div>
		<div class="metacontent">

		<div class="links"><strong>Links:</strong> <span class="metacontent list"><ul class="metacontent list"><li><a href="/pr/2006-Sep-About-Mike-Cook" title="Read the rest of this posting." class="read-more">read more</a></li></ul> </span></div>					</div>
	</div>
</div>

Any suggestions?