rbtrace: Can't install gem on OSX 10.5.8

Can’t install the gem on my OSX laptop. Details below. Let me know if you need more info.

OSX 10.5.8 $ ruby -v ruby 1.8.7 (2008-08-11 patchlevel 72) [i686-darwin9]

$ sudo gem install rbtrace Building native extensions. This could take a while… ERROR: Error installing rbtrace: ERROR: Failed to build gem native extension.

/opt/local/bin/ruby extconf.rb – tar zxvf msgpack-0.5.4.tar.gz – ./configure --disable-dependency-tracking --disable-shared --disable-cxx --with-pic --prefix=/opt/local/lib/ruby/gems/1.8/gems/rbtrace-0.3.12/ext/dst/ *** 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.

Provided configuration options: –with-opt-dir –without-opt-dir –with-opt-include –without-opt-include=${opt-dir}/include –with-opt-lib –without-opt-lib=${opt-dir}/lib –with-make-prog –without-make-prog –srcdir=. –curdir –ruby=/opt/local/bin/ruby extconf.rb:6:in sys': ./configure --disable-dependency-tracking --disable-shared --disable-cxx --with-pic --prefix=/opt/local/lib/ruby/gems/1.8/gems/rbtrace-0.3.12/ext/dst/ failed, please report to https://github.com/tmm1/rbtrace/issues (RuntimeError) from extconf.rb:35 from extconf.rb:31:inchdir’ from extconf.rb:31 from extconf.rb:27:in `chdir’ from extconf.rb:27