named using 50% CPU suddenly for unknown reason?

[Adrian NoSpm!]

Hi,

My primary and secondary DNS servers jumped their load average up 3 times
in one morning last week and I can't work out why.   I'm using different 
versions,
8.3.3-REL being the latest.  the named processes are running constantly at ~ 
50%

It's not a DOS issue (i've been watching the switch), sockstat shows a
normal number of connections to named and the named log file and my syslog
doesn't show anything unusual..  Stopping the secondary DNS doesn't effect
the primary (and visaversa)..

I reverted back to a config file from when everything was ok and that didn't 
help!
Can anyone suggest what else I could look into?

Thanks,
Adrian.

_________________________________________________________________
Get mobile Hotmail. Go to  http://ninemsn.com.au/mobilecentral/signup.asp