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.