updateinterval option appears to be broken

I'm currently evaluating replacing our ntpd classic machines with ntpsec, and the -U option we're using appears to be broken. Due to having some systems with a large number of VIPs that caused ntpd to chew up a lot of CPU during the update cycles, we disable the updates using -U0. This fails in newer versions of ntpsec:

# ./ntpd -U0
Unknown command line switch or missing argument.
USAGE:  ntpd [ -<flag> [<val>] | --<name>[{=| }<val>] ]...
  Flg Arg Option-Name    Description
   -4 no  ipv4           Force IPv4 DNS name resolution
				- prohibits the option 'ipv6'
   -6 no  ipv6           Force IPv6 DNS name resolution
				- prohibits the option 'ipv4'
   -c Str configfile     configuration file name
   -d no  debug-level    Increase output debug message level
				- may appear multiple times
   -D Str set-debug-level Set the output debug message level
				- may appear multiple times
   -f Str driftfile      frequency drift file name
   -g no  panicgate      Allow the first adjustment to be Big
				- may appear multiple times
   -h no  --help         Display usage summary of options and exit.
   -i Str jaildir        Jail directory
   -I Str interface      Listen on an interface name or address
				- may appear multiple times
   -k Str keyfile        path to symmetric keys
   -l Str logfile        path to the log file
   -L no  novirtualips   Do not listen to virtual interfaces
   -m no                 Enable mDNS registration
   -n no  nofork         Do not fork
   -N no  nice           Run at high priority
   -p Str pidfile        path to the PID file
   -P Num priority       Process priority
   -q no  quit           Set the time and quit
   -r Str propagationdelay Broadcast/propagation delay
   -s Str statsdir       Statistics file location
   -t Str trustedkey     Trusted key number
				- may appear multiple times
   -u Str user           Run as userid (or userid:groupid)
   -U Num uinterval      interval in secs between scans for new or dropped interfaces
      Str var            make ARG an ntp variable (RW)
				- may appear multiple times
      Str dvar           make ARG an ntp variable (RW|DEF)
				- may appear multiple times
   -x no  slew           Slew up to 600 seconds
   -V no  version        Output version information and exit
   -h no  help           Display extended usage information and exit


# ./ntpd -U
Segmentation fault (core dumped)

That test was run with 0.9.7, but head appears to exhibit the same problem.

Going back to 0.9, -U0 worked but -U had the same core dump behavior. It looks like 0.9.4 may have been the first release problem to fail on -U0.