error- master file: out of zone ?

[scratch]

> Now, my DNS won't return an authorititive answer, and I can't figure out
why. It seems there is a problem with my zone file, some thing to do with
being "out of range". Heres a couple of lines from my log file.......
>
> dns_rdata_fromtext: teawamutu.net.db:3: near '7200': out of range
> dns_zone_load: zone teawamutu.net/IN: loading master file teawamu.net.db:
out of range


> TTL    86400
> @               IN      SOA     pc9.scratch.net.nz.     wmedia.xtra.co.nz.
(
>                                 20020103016     ; serial
>                                 7200            ; refresh       - 2 hours
>                                 7200            ; retry         - 2 hours
>                                 604800          ; expire        - 7 days
>                                 7200 )          ; default_ttl   - 2 hours
>
>                 IN      NS      pc9.scratch.net.nz.
>                 IN      NS      ns2.nameserver.net.nz.
>
> www             IN      A       210.86.2.21
> @               IN      A       210.86.2.21
>

Is it because the serial is too big? ie: YYYYMMDDNNN......one too many N's?
If so, how to I shorten it?

Richard.