udev has changed the rule syntax.
See /usr/share/doc/udev-*/RELEASE-NOTES and man udev(7)
Please review your udev rules and change:
BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS
Fixed this by fixing upstream in libmtp 0.2.0.
Could you check to see if it's still sound Harald?