[hdrolling]

When you start a thread or comment on someone else's on the bottom of you comment before you hit submit reply there will be two buttons "Post Quick Reply" and "Go Advanced".

If you go advanced you will then see further down the option to "manage attachments", click that and you can pic a pic from your computer (up to 5 per-comment)

After you choose a file hit upload and then replay and your pic will be added to the post or your comment.