Medusa was previously distributed under a 'free for non-commercial use' license. In May of 2000 I changed the license to be identical to the standard Python license. The standard Python license has always applied to the core components of Medusa, this change just frees up the rest of the system, including the http server, ftp server, utilities, etc..
I would like to take this opportunity to thank all of the folks who supported Medusa over the years by purchasing commercial licenses.
-Sam