I've done some additional research, and it seems to be a matter of permissions: using the scanner under the root account (both with scanimage and under GUI programs) works like a charm.
------------------------------ Andreas Rönnquist escribió el lun, 23 sep 2013 16:28 ART: >Do you have the package scanbuttond installed? See #598102 at >http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=598102 , which could >be the problem you run into. > >(In that case, removing the scanbuttond package should solve the >problem and make the scanner usable again, but that unfortunately makes >the buttons on the scanner useless, you'll have to operate it through >software like sane instead.) > >-- Andreas Rönnquist >gus...@gusnan.se -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org