Sendmail host lookup problem

[Hexren]

I have a LAN in the 192.168.0 range. I am trying to send mail from
192.168.0.78 (gc-infra.steenbuck.net) to 192.168.0.29
(bettchen.steenbuck.net).
This leeds to 550 errors. "Host unknown (Name server: bettchen.steenbuck.net: host not found)"

192.168.0.29 is also acting as my DNS Server. Both machines have correct (or so I hope) entries in the nameserver. I can dig their names and
"dig -x" their pointers. Be aware of the fact
that I am not the owner of steenbuck.net and just tell my own machines
that I am because I like the name.

Interestingly adding "192.168.0.29 bettchen bettchen.steenbuck.net" to /etc/hosts
solves my problem.

I sniffed the network and gc-infra does the same in both cases. It
asks DNS for the IP of bettchen and gets it. Only when bettchen is in
/etc/hosts it then sends the mail otherwise not.

I've googled around a bit and searched the list and found similiar
problems:
http://lists.freebsd.org/pipermail/freebsd-questions/2004-December/068127.html
Only I do not have any kind if W2K in my LAN. And the DNS
server is FreeBSD (BIND).

I am lost. Has anybody an idea how I can investigate further into my
problem.

Thanks
Hexren


Attachments:
maildmp_dns    :ethereal compatible dump without target host
(bettchen) in /etc/hosts

maildmp_hosts  :ethereal compatible dump with target host
(bettchen) in /etc/hosts
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