For some reason I edited motd file yesterday from the standard "Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY..." to my own customized message. After a system restart today, my customized message is gone and it's back to:
The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.
Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
How can I make my own message permanent? BTW, I am using Debian 6.