CSS: clear: left working too well?

Question

I have an issue every now and again and I'm not sure what the solution is.

I have a 2 column layout (left strit, and then main area). In the main area, I sometimes have a secondary 2 column layout (eg - for a news section, where there is an icon, and then the news item). When I clear left on the new item, instead of clearing the image above it (which is left floated) it clears the nav bar on the left.

Here is a sample. This seems to be an issue on FF3.6, whereas IE8 seems fine.