Whether dtlogin is started or not is settable with /usr/dt/bin/dtconfig As dtlogin itself explain when invoked without arguments:
/usr/dt/bin/dtconfig -d (disable auto-start) /usr/dt/bin/dtconfig -e (enable auto-start) /usr/dt/bin/dtconfig -kill (kill dtlogin) /usr/dt/bin/dtconfig -reset (reset dtlogin) /usr/dt/bin/dtconfig -p (printer action update) /usr/dt/bin/dtconfig -inetd (inetd.conf /usr/dt daemons) /usr/dt/bin/dtconfig -inetd.ow (inetd.conf /usr/openwin daemons)