The copyright notices in each source file look very restrictive compared to the original author's source code.
While his source code was lacking license details the documentation states LGPL:
© Copyright 2001, 2002, 2003, 2004 dr. Cristiano Sadun under LGPL
Is it possible to change your repo's source to a more open source license so that people can take advantage of your bug fixes and mavenization of the project?