Hi, I also stacked on the TwitPic's OAuth Echo Protocol a week ago.
The point was making header just like to request Twitter. 1. make OAuth Header to request Account/Verify_credentials to get JSON not XML as result by GET method. 2. insert this header into X-Verify-Credentials-Authorization header with realm. You make verification request header, and TwitPic send it to Twitter as you send in TwitPic site. Remember the OAuth Echo was just an echo protocol. The image file to send to TwitPic should be included as multipart/form- data format. I wrote a blog article for Ruby language and hope the code in the article make some help. -- Norio Suzuki
