I did it and it WORKS! VERY simple to do.
Download the AirPrint Activator, install (as admin) the corresponding version (32bit or 64bit), share your printer via Windows, turn ON your Guest account, have your iPhone, iPad and or iPod Touch on WiFi and send your job to PRINT!
When you print for the first time, you’ll be prompted for a username and password, simply enter ‘Guest’ as username and leave the password field blank.
So simple, it takes one sentence to describe the whole process.
NEW DOWNLOAD LINK, ENGLISH VERSION: https://rapidshare.com/files/457837624/AirPrint-Activator-EN.rar
Step1: Choose the operating system you use.
Step 2: Open “printer” in the control panel. Rightclick on your printer and choose “properties”. Choose the [something like] permission tab and permit the printer. [ I dont know how the buttons are exactly called on english windows but i hope it helps u out :D]
Step3: Make sure your firewall allows Airprint in [Path].Hope it helps you!
(thank you to YouTube user: MrShneedleWoods for translation)