Oder gleich so:
# cp /etc/inet/ntp.client /etc/inet/ntp.conf
und dann aendern, dass sie so ausschaut wie bei mir

# cat /etc/inet/ntp.conf
# ident "@(#)ntp.client 1.3 00/07/17 SMI"
#
# /etc/inet/ntp.client
#
# An example file that could be copied over to /etc/inet/ntp.conf; it
# provides a configuration for a host that passively waits for a server
# to provide NTP packets on the ntp multicast net.
#
multicastclient 224.0.1.1
server 0.de.pool.ntp.org
server 1.de.pool.ntp.org
server 2.de.pool.ntp.org
und dann geht's los
# svcadm enable ntp