This is a fork/version of FT Jam which includes bug fixes for Windows as well as improved docs for Unix.
Other versions of Jam are:
- original Jam version http://www.perforce.com/documentation/jam NOTE in August 2014 Perforce released a new version 2.6 which includes old (until August private?) changes see https://swarm.workshop.perforce.com/projects/perforce_software-jam/changes/ for more information see https://swarm.workshop.perforce.com/files/guest/perforce_software/jam/src/RELNOTES?v=67
- FT Jam is originally from the FreeType project http://www.freetype.org/jam/index.html
- David from the FreeType project was at one point maintaining a fork at http://david.freetype.org/jam/ I've been unable to get a response from him. This project https://bitbucket.org/clach04/ftjam/ includes all the enhancements from David's version (plus some extra, see https://bitbucket.org/clach04/ftjam/commits)
- Boost.Jam http://sourceforge.net/projects/boost/files/boost-jam/ from the Boost C++ project. If you need to support old versions of Windows (pre Windows XP, pre Windows 5.0) this version has support, https://bitbucket.org/clach04/ftjam assumes Windows XP and higher after change https://bitbucket.org/clach04/ftjam/commits/6261465365eeb70716ca297f1faea58939ae5ff1) it also appears to have a Windows retry fix by Bronek Kozicki which is similar to the one included in this project.
- JamPlus http://jamplus.org/ - this one has a number of new features, an interesting one is exporting project files for CodeBlocks, Microsoft Visual Studio, and XCode more information at http://jamplus.org/projects/jamplus/wiki