Because mingw's version of GCC only "likes" paths with '/' 's building of buildr "from source" in windows with mingw fails (well, in reality rjb fails).
c:/ruby/bin/ruby.exe extconf.rb checking for jni.h... *** extconf.rb failed *** Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options. Gem files will remain installed in c:/ruby/lib/ruby/gems/1.9.1/gems/rjb-1.1.6 for inspection. Results logged to c:/ruby/lib/ruby/gems/1.9.1/gems/rjb-1.1.6/ext/gem_make.out possible fixes: I could commit a patch for extconf.rb or the distributor could use the http://github.com/luislavena/rake-compiler/tree/master rake compiler to generate binaries for the several platforms [this one is 1.9.1 on doze]. Thanks! -r
