=net-misc/modemmanager-1.4.8 does not install anymore a unit file, so the service is not started. The result is that NetworkManager does not see my usb network adapter. From an irc discussion: 17:55 <+dwfreed> ago: looks at the diffs of the tarballs, they generated the Makefile.in on 1.4.8 with a newer version of automake; this probably broke something
I cannot reproduce this; for me, modemmanager-1.4.8 installs /usr/lib/systemd/system/ModemManager.service both in ~amd64 and in a stable amd64 chroot. Please attach your complete build log.
After recompiling it I see the unit file here O_O
Maybe it was due to some parallel make problems. They should be solved in 1.4.12 (and probably some older version too)