upsdrvctl is called from "${nut_prefix}/libexec/nut/upsdrvctl" in the init scripts. The UPGRADING-file however mentions upsdrvctl has been moved to sbin/, so the script fails. Changing the path to "${nut_prefix}/sbin/upsdrvctl" in the initscript fixes the problem.
Over to maintainer.
Over to maintainer
Fixed by r360718 on 2014-07-04 21:51:06 -0700 (Fri, 04 Jul 2014).