I tried this one.
Not tested very deeply, so... use at your own risk, if you have a test board better. 
There is a bit of css to add to portal.css:
.sp_article_content .sp_attachment_thumb {
	float: left;
	margin-right: 10px;
}
.sp_article_content .post:after {
	content: '';
	display: block;
	width: 100%;
	clear: both;
}
Ohhh... darn!
I just realized this works only for the development branch... darn!
Tomorrow I'll see to backport it to the current stable version.