This is an unsupported variant, as x86 is the only CPU architecture being targeted for R1. It is provided for development and testing purposes only. Releasing software that requires these unsupported builds is discouraged.
The SPARC port is in an extremely early state. The kernel may load but a
lot of work still needs done before you can get a desktop.
For more information on missing packages, image and archive formats, etc., please refer to this site's main page.
Unsupported SPARC Builds