ntp is bugging my named?

Hi,

my named stops several times per day and the /var/log/messages says:

Jul  2 00:59:24 tesla named[14742]: transfer of
'infomedicsportal.com/IN' from 193.78.30.50#53: failed while receiving
responses: permission denied
Jun 13 21:14:57 tesla ntpd[16699]: time reset +6.159713 s
Jun 13 21:14:57 tesla ntpd[16699]: frequency error 5636 PPM exceeds
tolerance 500 PPM
Jun 13 21:15:00 tesla named[14742]:
/usr/src/usr.sbin/bind/lib/isc/unix/time.c:239: INSIST(t1->nanoseconds <
1000000000 && t2->nanoseconds < 1000000000) failed
Jun 13 21:15:00 tesla named[14742]: exiting (due to assertion failure)
Jul  2 01:09:45 tesla ntpd[16699]: time reset +6.125444 s
Jul  2 01:09:45 tesla ntpd[16699]: frequency error 5579 PPM exceeds
tolerance 500 PPM

Is this a known problem?

Raymond.