If you dont know Ubiboot is a boot manager for N9(50) devices. Using the example configuration it is fairly easy to hexa-boot the device between Harmattan/
Systems, and change kernels.
According to Juice Me, There are many people who are having trouble when setting up ubiboot environment correctly, He
released a special SailfishOS-version of ubiboot-02-0.3.5
This archive contains an ubiboot setup specifically tailored to boot
the SailfishOS/N9 configuration.
The resulting ubiboot menuscript contains only 2 icons, one for SailfishOS
and one for Harmattan. Both icons autoboot into the specified OS.
Read the full text here http://www.swagman.org/juice/ubiboot/ubiboot_for_sailfish/README.txt
Download Ubiboot http://www.swagman.org/juice/ubiboot/ubiboot_for_sailfish/ubiboot-02_0.3.5_131213_SFOS.tar