Hmmm… I’d probably not say, it was their only their buildsystem, but also the only means of official distribution.
Have you checked if there is any other linux distribution that packages this application, how do they deal with it?
Also, they seem to tag irregularly… The last tag is 1.6.15, the version file says 2.3.1.0… Just from looking at HEAD, I can not really figure out, if that is, what will be released as 2.3.1 in the future or if 2.3.1 has been the last release…