You can then add this PID at a Mobipocket vendor site and redownload books with Kindle's PID enabled. Kindlepid.py generates Mobi PID from Kindle serial number. Linked archive includes two Python scripts. After fixing that, I could read the book on Kindle. AZW files have a flag set in the DRM info which is not present in books bought from other vendors. Well, I've discovered the algorithm used to generate the PID and was able to use it on Fictionwise, but there was another catch. We've known for some time already that Amazon's AZW files are actually Mobi files, but Amazon didn't share Kindle's Mobi PID which would allow one to buy encrypted Mobi books for Kindle.
