No printing: Gentoo + Gutenprint 5.3.3-r2 + Canon Maxify MB5150

Greetings,

having just replaced my old Canon Pixma MX885 with a Canon Maxify MB5150
I find myself not being able to print to this printer from Gentoo (works
from Windoze, however, so it's not the printer).

Printing a test page directly from within Cups on Gentoo  prints a light
grey "Printer Test Page" line  on the first sheet  picked from the paper
tray and then moves all paper  from the source paper tray  to the output
paper tray until the former is empty.   And when printing a one page PDF
from within Okular  it doesn't print anything at all  but directly moves
all paper from the input to the output tray.

File "/var/log/cups/error.log"  does contain entries,  but none that did
not already occur with the old Pixma.

Does this sound familiar to anyone?  

Any hints appreciated ...

Sincerely,
  Rainer