Não consigo instalar a gema mysql2 no meu sistema Windows7 x64. Tentei usar as versões de 32 e 64 bits do servidor MySQL, mas nenhuma me levou mais long

Instalei o Ruby 1.8, o kit de desenvolvimento e a plataforma Rails. Até instalei o minGW para permitir a compilação de C ++ / C. O MySQL Server foi instalado no local padrão.

Ao executar o comando:

C:\Users\Arne>gem install mysql2 -- --with-mysql-include="C:\Program Files (x86)\MySQL\MySQL Server 5.1\include" --with-mysql-lib="C:\Program Files (x86)\MySQL\MySQL Server 5.1\lib\"

Eu recebo a seguinte saída do console:

Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
*** 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:/Ruby/bin/ruby
        --with-mysql-dir
        --without-mysql-dir
        --with-mysql-include=${mysql-dir}/include
        --with-mysql-lib=${mysql-dir}/lib
        --with-libmysqllib
        --without-libmysqllib
ERROR:  Error installing mysql2:
        ERROR: Failed to build gem native extension.

        C:/Ruby/bin/ruby.exe extconf.rb --with-mysql-include=C:\Program Files (x
86)\MySQL\MySQL Server 5.1\include --with-mysql-lib=C:\Program Files (x86)\MySQL
\MySQL Server 5.1\lib"
checking for rb_thread_blocking_region()... no
checking for main() in -llibmysql... no


Gem files will remain installed in C:/Ruby/lib/ruby/gems/1.8/gems/mysql2-0.3.2 f
or inspection.
Results logged to C:/Ruby/lib/ruby/gems/1.8/gems/mysql2-0.3.2/ext/mysql2/gem_mak
e.out

A saída do meu ambiente de acordo com Rubygems é:

C:\Users\Arne>gem env
RubyGems Environment:
  - RUBYGEMS VERSION: 1.7.2
  - RUBY VERSION: 1.8.7 (2011-02-18 patchlevel 334) [i386-mingw32]
  - INSTALLATION DIRECTORY: C:/Ruby/lib/ruby/gems/1.8
  - RUBY EXECUTABLE: C:/Ruby/bin/ruby.exe
  - EXECUTABLE DIRECTORY: C:/Ruby/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86-mingw32
  - GEM PATHS:
     - C:/Ruby/lib/ruby/gems/1.8
     - C:/Users/Arne/.gem/ruby/1.8
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :benchmark => false
     - :backtrace => false
     - :bulk_threshold => 1000
  - REMOTE SOURCES:
     - http://rubygems.org/

As seguintes gemas também foram instaladas no sistema:

C:\Users\Arne>gem list --local

*** LOCAL GEMS ***

abstract (1.0.0)
actionmailer (3.0.7)
actionpack (3.0.7)
activemodel (3.0.7)
activerecord (3.0.7)
activeresource (3.0.7)
activesupport (3.0.7)
arel (2.0.9)
builder (3.0.0, 2.1.2)
bundler (1.0.12)
erubis (2.7.0, 2.6.6)
fastthread (1.0.7)
i18n (0.5.0)
mail (2.3.0, 2.2.18)
mime-types (1.16)
mysql (2.8.1 x86-mingw32)
polyglot (0.3.1)
rack (1.2.2)
rack-mount (0.7.2, 0.6.14)
rack-test (0.5.7)
rails (3.0.7)
railties (3.0.7)
rake (0.8.7)
rdoc (3.5.3, 2.5.11)
rdoc-data (2.5.3)
rubygems-update (1.7.2)
thor (0.14.6)
treetop (1.4.9)
tzinfo (0.3.27, 0.3.26)

Não sei o que está faltando ou está errado, mas os arquivos de saída apontados pelo script contêm os seguintes dados:

mkmf.log:

have_func: checking for rb_thread_blocking_region()... -------------------- no

"gcc -o conftest -I. -IC:/Ruby/lib/ruby/1.8/i386-mingw32 -I.    -g -O2 -DFD_SETSIZE=256    conftest.c  -L. -LC:/Ruby/lib -L.      -lmsvcrt-ruby18-static  -lshell32 -lws2_32  "
conftest.c: In function 't':
conftest.c:7:53: error: 'rb_thread_blocking_region' undeclared (first use in this function)
conftest.c:7:53: note: each undeclared identifier is reported only once for each function it appears in
checked program was:
/* begin */
1: #include <ws2tcpip.h>
2: #include <winsock2.h>
3: #include <windows.h>
4: 
5: /*top*/
6: int main() { return 0; }
7: int t() { void ((*volatile p)()); p = (void ((*)()))rb_thread_blocking_region; return 0; }
/* end */

"gcc -o conftest -I. -IC:/Ruby/lib/ruby/1.8/i386-mingw32 -I.    -g -O2 -DFD_SETSIZE=256    conftest.c  -L. -LC:/Ruby/lib -L.      -lmsvcrt-ruby18-static  -lshell32 -lws2_32  "
C:\Users\Arne\AppData\Local\Temp\ccCicaNu.o: In function `t':
C:\Ruby\lib\ruby\gems\1.8\gems\mysql2-0.3.2\ext\mysql2/conftest.c:3: undefined reference to `rb_thread_blocking_region'
collect2: ld returned 1 exit status
checked program was:
/* begin */
1: /*top*/
2: int main() { return 0; }
3: int t() { rb_thread_blocking_region(); return 0; }
/* end */

--------------------

have_library: checking for main() in -llibmysql... -------------------- no

"gcc -o conftest -I. -IC:/Ruby/lib/ruby/1.8/i386-mingw32 -I. -IC:\Program    -g -O2 -DFD_SETSIZE=256    conftest.c  -L. -LC:/Ruby/lib -LC:\Program -L.      -lmsvcrt-ruby18-static -llibmysql  -lshell32 -lws2_32  "
c:/mingw/bin/../lib/gcc/mingw32/4.5.2/../../../../mingw32/bin/ld.exe: cannot find -llibmysql
collect2: ld returned 1 exit status
checked program was:
/* begin */
1: #include <ws2tcpip.h>
2: #include <winsock2.h>
3: #include <windows.h>
4: 
5: /*top*/
6: int main() { return 0; }
7: int t() { void ((*volatile p)()); p = (void ((*)()))main; return 0; }
/* end */

"gcc -o conftest -I. -IC:/Ruby/lib/ruby/1.8/i386-mingw32 -I. -IC:\Program    -g -O2 -DFD_SETSIZE=256    conftest.c  -L. -LC:/Ruby/lib -LC:\Program -L.      -lmsvcrt-ruby18-static -llibmysql  -lshell32 -lws2_32  "
c:/mingw/bin/../lib/gcc/mingw32/4.5.2/../../../../mingw32/bin/ld.exe: cannot find -llibmysql
collect2: ld returned 1 exit status
checked program was:
/* begin */
1: /*top*/
2: int main() { return 0; }
3: int t() { main(); return 0; }
/* end */

--------------------

gem_make.out:

C:/Ruby/bin/ruby.exe extconf.rb --with-mysql-include=C:\Program Files (x86)\MySQL\MySQL Server 5.1\include --with-mysql-lib=C:\Program Files (x86)\MySQL\MySQL Server 5.1\lib"
checking for rb_thread_blocking_region()... no
checking for main() in -llibmysql... no

Espero que alguém possa apontar o que estou fazendo de errado ou o que realmente está faltando no meu sistema de desenvolvimento para instalar e instalar esta joia corretament