Class means that it has to be defined soemwhere else. I'm not sure if your on myspace or something, but I've seen other posts from you there. When your stating class "box2M", it's saying "Look for the tag called 'box2M' and set its properties likewise." There may not be a box3M.
Two divs can not go on the same line unless there is a code that tells it to.
You don't want them to be on the same line.
Try closing your div tags?
<a href="/f5dudeandy">Some text blah blah</a>
<a href="/f5dudeandy">More text</a>