Here are the procedures for launching the dedicated server. At this time there are no options nor controls for the server, it just runs as the communication medium for the clients that connect (you can't change the default port, nor can you save campaigns from the server).
download the .zip file and unpack it into a directory.
Run the following commands, the first bits set up the start-server.sh script, which only needs to be done once. The last line would be re-run each time you want to bring up the server.
cat <<EOF > start-server.sh
# This script will start the dedicated server on a Linux box.
CLASSPATH="`echo maptool*.jar lib/*.jar | sed -e 's/ /:/g'`" exec java net.rptools.maptool.server.MapToolServer
chmod 755 start-server.sh
Minor clarification "can't save campaigns from the server" is true, but any connection GM to the server can load and save campaigns.
Also, a startup script will be provided in 1.0 that will work for a variety of platforms.