Edit your “/etc/apt/sources.list”.

Add one of the following lines, depending of your Debian distribution:

#For etch distribution :

deb http://www.openser.org/debian etch main

#For sarge distribution :

deb http://www.openser.org/debian sarge main

#For sid distribution :

deb http://www.openser.org/debian sid main

Note that all APT repositories contain the packages for 'i386' architectures and the one for 'sid' distribution contains packages for 'amd64' as well.

Then run:

apt-get update
apt-get install openser

That's it.

To see all available packages for OpenSER do:

apt-cache search openser

To see details about OpenSER package do:

apt-cache show openser

How about the message “WARNING: The following packages cannot be authenticated!” How can I install the key with 'apt-key'? And where is this key? If anybody this, please include this info here and then remove this question.