This is a sim­ple work­ing con­fig­u­ra­tion method posted in the com­ments of this page. The page is offline but I found it in Google Cache and ver­i­fied that it works. Repost­ing it here for posterity.

NTP client setup on SOLARIS 10:
============================================
1. cp /etc/inet/ntp.server /etc/inet/ntp.conf
2. vi /etc/inet/ntp.conf add the IP (exam­ple 10.10.10.1) of the "server" and com­ment out `fudge 127.127.XType.0 stra­tum 0`
NOTE: file is trun­cated — some header com­ments cut out

# Either a peer or server. Replace "XType" with a value from the
# table above.
server pool.ntp.org # or a local NTP server IP like 10.10.10.1
#fudge 127.127.XType.0 stra­tum 0

broad­cast 224.0.1.1 ttl 4

enable auth mon­i­tor
drift­file /var/ntp/ntp.drift
stats­dir /var/ntp/ntpstats/
file­gen peer­stats file peer­stats type day enable
file­gen loop­stats file loop­stats type day enable
file­gen clock­stats file clock­stats type day enable

keys /etc/inet/ntp.keys
trust­ed­key 0
requestkey 0
con­trolkey 0

3. touch /var/ntp/ntp.drift
4. svcadm enable ntp or svcadm restart ntp
5. Check if NTP is online

myhost:~) svcs ntp
STATE STIME FMRI
online 21:11:54 svc:/network/ntp:default

6. Ver­ify:

myhost:~) ntpq –p

remote           refid      st t when poll reach   delay   offset    disp
==============================================================================
NTP.MCAST.NET   0.0.0.0         16 u    -   64    0     0.00    0.000 16000.0
216.45.57.38    clock.via.net    2 u   30   64    3    59.39  -92.576 7902.57