bind-8.2.2-P5 keeps loading primary zones unnecessarily

[jpsp at oberon.fccn.net]

Hello all

I have a bind-8.2.2-P5 running chroot to some dir.   All seems to
work fine except for one primary zone that keeps being loaded
unnecessarily.

I've got about 900 messages like these only for today :

22-Dec-1999 20:42:25.531 master zone "XXXXXXXX" (IN) loaded (serial 1999122201)

The zone's serial number is unchanged on all loads, and secondary name
servers are being notified.  Every thing seems to be ok on the zone 
itsef (it's a little big though : 1MB).  

The following messages appear in all such loads :

  Zone "XXXX" (file primary/XX.): No default TTL set using SOA minimum instead
  master zone "XX" (IN) loaded (serial 1999122201)
  suppressing duplicate notify ("XX" IN SOA)

Sometimes there's more than one load in the same second!  Can someone
remotely induce bind to load a primary zone ?  If so, something is
bound to appear on the logs...

I had no such problem with the same file, same machine and OS, on a bind-8.1.2.

Any ideas ?
Any debugging hints ?

Thanks,
Joao Pagaime