Perfect hierzo, syncen vanuit cron...
# m h dom mon dow command
0 * * * * /usr/sbin/ntpdate ntp.ubuntu.com | logger
1 * * * * /sbin/hwclock -w
Feb 28 22:00:01 lt9 CRON[8341]: (root) CMD (/usr/sbin/ntpdate ntp.ubuntu.com | logger)
Feb 28 22:00:09 lt9 logger: 28 Feb 22:00:09 ntpdate[8342]: adjust time server 91.189.94.4 offset 0.000756 sec
Feb 28 22:01:01 lt9 CRON[8360]: (root) CMD (/sbin/hwclock -w)