The emerge log for sys-fs/udev-189 wrote: "This version of udev moves the files that were installed in /lib/udev to /usr/lib/udev. We include a backward compatibility patch for gentoo to allow the rules in /lib/udev/rules.d to be read. However, bugs should be filed against packages that are installing files in /lib/udev so they can be fixed." media-libs/libgphoto2-2.4.14 installs files into that old location, so it should be fixed. Remerging the package is not enough to fix this issue. This might be related to bug #374989.
revbump in ~ərch, but not for 2.5 series since it's hardmasked: +*libgphoto2-2.4.14-r1 (04 Sep 2012) + + 04 Sep 2012; Samuli Suominen <ssuominen@gentoo.org> + +libgphoto2-2.4.14-r1.ebuild, libgphoto2-2.5.0.ebuild: + Query the value of udevdir from udev.pc pkg-config file wrt #433908 by Martin + von Gagern http://sources.gentoo.org/viewvc.cgi/gentoo-x86/media-libs/libgphoto2/libgphoto2-2.5.0.ebuild?r1=1.2&r2=1.3