DNS problem

[Andreas Tille <tille@physik.uni-halle.de>]

Hello,

while trying to configure exim via 
  dpkg --configure exim

I've got the message:

Setting up exim (2.05-1 ...
Error: system's FQDN hostname (wr_linux01.rki.de) doesn't match
RFC1035 syntax; cannot configure the mail system.

The host isn't inserted into the DNS yet.  How can I solve this
problem temporarily because the maintainer of this service is not
available at this moment.

(Sorry for asking debian-user related question here, but I4m sitting
behind a really slow Win-NT modem and are quite happy to get
my telnet work at all.  I don't want to to subscribe a new list
for that purpose.  Thanks.)

Kind regards

      Andreas.