Why is BIND responding with 2 SOA records???

[nobody]

Hello,

        I have two nameservers setup with one as the primary and one as the
        secondary for a number of zones.  Until just a few days ago, 
        everything was running smoothly on BIND 8.2.2P5.  I updated a zone
        file on the primary server and restarted the secondary so that it 
        would pull a fresh copy.  The secondary did receive the updated data,
        but it left an error message in the syslog:

Dec  9 15:22:45 mail named[3771]: Zone "manteca.net" (file slave/manteca.net): 
multiple SOA RRs found
Dec  9 15:22:45 mail named[3771]: slave zone "manteca.net" (IN) rejected due 
to errors (serial 1999100800)

        I checked the zone file format and found it to be correct, only one
        SOA record.  I then erased all of the data files on the secondary
        server and restarted named to find out if any other zones were having
        the same problem.  All of them were rejected, even those that I 
        haven't touched for months.  I had a closer look using nslookup and
        queried the primary for an SOA record for any domain, and here's
        what I got:

> ls -t SOA manteca.net
[ns1.valleyip.net]
$ORIGIN manteca.net.
@                       1D IN SOA       ns1.valleyip.net. dns.valleyip.net. (
                                        1999100800      ; serial
                                        3H              ; refresh
                                        1H              ; retry
                                        1W              ; expiry
                                        1D )            ; minimum

                        1D IN SOA       ns1.valleyip.net. dns.valleyip.net. (
                                        1999100800      ; serial
                                        3H              ; refresh
                                        1H              ; retry
                                        1W              ; expiry
                                        1D )            ; minimum

        Am I missing something in the configuration file?  Has anyone else
        ever seen this?  Any help will be very greatly appreciated.

        Thank you,
        ~brian