Hi,
For people who are interested, i give you the way to start twonkymedia server under Debian and Ubuntu automatically.
For a default installation (/usr/local/twonkymedia)
Copy the twonkymedia.sh script in /etc/init.d/ (in root mode or with sudo obviously)
Then create the symbolic links.
For Ubuntu (tried with 8.04 until 10.10) type these commands
sudo ln -s /etc/init.d/twonkymedia.sh /etc/rc2.d/S99mediaserver
sudo ln -s /etc/init.d/twonkymedia.sh /etc/rc6.d/K99mediaserver
sudo ln -s /etc/init.d/twonkymedia.sh /etc/rc0.d/K99mediaserver
For Debian (tried with 4 and 5) type these commands in root mode
ln -s /etc/init.d/twonkymedia.sh /etc/rc2.d/S99mediaserver
ln -s /etc/init.d/twonkymedia.sh /etc/rc6.d/K99mediaserver
ln -s /etc/init.d/twonkymedia.sh /etc/rc0.d/K99mediaserver
Enjoy