Video embedding nests improperly

The embedding of videos (from the media server) seems to deliver a wrongly nested html.

Here's an example:
http://www.curriki.org/xwiki/bin/view/Coll_kathyduhl/GraphingInequalities

One can easily see that the first box only closes on the bottom when following the thin-hair-borders. One can also see in firebug that the

div class="sub-asset-wrapper category-video"

contains the below video.