Seems it's specific to trackpoints (thinkpad nipples), not mouse wheels,
so updated accordingly and linked to upstream bug.
** Bug watch added: GNOME Bug Tracker #778783
https://bugzilla.gnome.org/show_bug.cgi?id=778783
** Also affects: eog via
https://bugzilla.gnome.org/show_bug.cgi?id=778
Thank you for taking the time to report this bug and helping to make
Ubuntu better. The issue you are reporting is an upstream one and it
would be nice if somebody having it could send the bug to the developers
of the software by following the instructions at
https://wiki.ubuntu.com/Bugs/Upstream/G
