Hardy Alpha2: HP Deskjet F370 not Scanning i.e. with Kooka

Version: Hardy Alpha2 LiveCD

My Printer (HP Deskjet F370) was not automatically detected.
When adding it via System Setting it prints the testpage quite o.k.
When starting HPLIB-Toolbox and installing the same printer again, it says (with green/user:root) that the printer is idle. Directly above this it says (with red / user=ubuntu) "Device communication error.".
(quite similar to this bug 144974)

Because the things shown green with root are o.k. i thought to add user "ubuntu" to the printer-group. But user Management does not work. (see separate Bugreport)

After this I started Kooka to scan something, but there was only my tv-card selectable as scan device.

PS: Installing XSane didn't change/help anything.
PS: Just contact me if you like to have all PrintScreen I made during this test.