You don't HAVE to use photobucket or Flickr. There's another way to post pictures. Here:
Notice when you reply to a message(or start a new thread), there's an optoin at the bottom of the page. Next to the "post" button, there's a "USE FULL EDITOR" button. Click on the "UFE" button and there should be a button that says "Browse". Then you can select files from your computer.
~Sometimes, the photo is too big. On some e-mail accounts, they'll let you adjust the size of your profile picture when you change it. I changed my profile picture and made the photo and tiny bit smaller, and just saved the smaller image onto the computer. Then it let me upload on here.
--Sorry, that explaination was REALLY confusing. I'm a confusing person. xD