Wrong port in example
The example code should have port '8080' which is the default.
So instead of
$ su stork-agent -s /bin/sh -c 'stork-agent register -u http://stork.example.org'
should be
$ su stork-agent -s /bin/sh -c 'stork-agent register -u http://stork.example.org:8080'
Edited by Slawek Figiel