It is however possible to re-enable that option by installing manually the files that were in the last beta:
- Download the files here: http://cl.ly/99eaa26e6a7273db9ca0
- You will have to install them in an invisible folder called 'usr'. you can make it appear by typing the following line in the Terminal:
open -a Finder /usr/
- Copy the content of the folder 'mime' into 'share/cups/mime/' and 'urftopdf' into 'libexec/cups/filter/'
this is where files should go:
- Remove your printer from the printing preferences
- add your printer again and activate printer sharing.
- If everything went well, you'll be able to print from an iOS 4.2 iDevice. Of course, there is certainly a reason why Apple didn't enable the option, and there could be some bug. If you choose to enable Airprint, we advise you to do a backup of your system in order to be able to go back in case of a problem.