Short description: When a system has a package that is obsoleted by some
package the channel up2date is running against, up2date does not offer to
upgrade it.

Long description: I was running up2date-2.7.2-7.x.6 (the one from 7.2) on a
mixed 7.1/7.2 system. The system had (among other things) the sane-1.0.3-10
package (from 7.1). Up2date did *not* offer to upgrade it to sane-frontends.

P.S. The system also had xsane-0.62-4 and xsane-gimp-0.62-4 (from 7.1)
installed. Up2date wanted to upgrade them to new xsane and xsane-gimp from
7.1 but failed complaining that a bunch of files from sane-backends (added
as a depenency of the new xsane* packages) conflicts with the sane-1.0.3-10
(the one that is obsoleted by sane-frontends which went unnoticed by up2date).