"the Software Development Kit (SDK) for the largely successful AmigaOS 4.1 Final Edition [...] enables third party developers to access all the enhancements and new features added in AmigaOS 4.1 Final Edition including: [...] - Extended memory which goes beyond the 4 GB memory barrier. [...]" http://www.hyperion-entertainment.biz/index.php/news/36-amigaos-4x/163