Umount isodevice before transferring control to the booted system

[Arbiel (gmx)]

Hi

When installing some distributions (xubuntu-12.04.2-desktop-i386 is an 
example ) from an iso file using the loopback command, the installation 
procedure reports it's unable to umount isodevice, and stops running.

I suppose this isodevice is seen as mounted because of grub.

Could you please, release the isodevice before transferring control to 
the booted system.

Best regards

Arbiel