As always it is a 'float: left' against images in your theme CSS file. Called, for some reason style.css.php… look for

it is the 'float: left;' statement that is cuasing your problem.

you can do whatever you want with it… careful though, as it could have repercussions on all of your non forum pages… I would try to make it do something diffferent in the forum… maybe add

.entry #sforum img {

float: none;

}

just add that after the statement Andy pointed out…

dont think so, but without doing it myself cant know for sure… since the forum directives come later, I would hope they override this one… when I edited his css file using firebug and made that change, it looked pretty good, but of course that was only on the page I was looking at… didnt try it for all pages… starting point…