Impossible d'installer la gemme MySQL2 sur Windows 7

J'obtiens le message d'erreur suivant lors de l'installation, laissez-moi savoir si j'ai besoin d'afficher plus de détails.

J'ai suivi les instructions à partir de l'emplacement suivant:
https://github.com/oneclick/rubyinstaller/wiki/Development-Kit

Je suis à l'aide de ruby 1.9.2p136 (2010-12-25) [i386-mingw32].

Voici ce que j'obtiens:

E:\work_desk\trunk>gem install mysql2 -v 0.2.4
Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing mysql2:
ERROR: Failed to build gem native extension.
C:/Ruby192/bin/ruby.exe extconf.rb
checking for rb_thread_blocking_region()... yes
checking for main() in -llibmysql... no
*** 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=C:/Ruby192/bin/ruby
--with-mysql-dir
--without-mysql-dir
--with-mysql-include
--without-mysql-include=${mysql-dir}/include
--with-mysql-lib
--without-mysql-lib=${mysql-dir}/lib
--with-libmysqllib
--without-libmysqllib
Gem files will remain installed in C:/Ruby192/lib/ruby/gems/1.9.1/gems/mysql2-0.
2.4 for inspection.
Results logged to C:/Ruby192/lib/ruby/gems/1.9.1/gems/mysql2-0.2.4/ext/mysql2/ge
m_make.out

source d'informationauteur Lohith MV