modemmanager can't be configured, claims upgrade from 15.04 to 15.10 beta failed

[S.]

Hi, I just upgraded from 15.04 to 15.10 beta using the Ubuntu 
update-manager tool. The update-manager got almost all the way to the 
end of the installation of the new packages, and then claimed that the 
upgrade failed because "modemmanager" package couldn't be configured. 
Fortunately the upgrade seems to have actually worked, but the errors 
are really ugly and shouldn't happen. After installation I ran another 
"apt-get upgrade" and it configured modemmanager just fine.