Apple is stonewalling open-source developers despite the company's recent release of much of the Mac OS X Tiger kernel source code, according to Proclus, administrator of the GNU-Darwin Distribution. "In order to have a free and open source system, two things are necessary. First, all the necessary source code must be obtainable by anyone, and second the system must obviously be bootable in order to use it," Proclus told MacNN. "Darwin OS is not bootable without the AppleACPIPlatform driver, which is closed source [and proprietary] at this time." On a related note, a slew of unannounced features have been posted to the web, found in the developer preview of Leopard.