fixing do_mysql hanging or install problems on mac os x

MerbなのでDataMapper。デフォルトDBはsqlite3だが、MySQL使う場合、do_mysqlをインストール
fixing do_mysql hanging or install problems on mac os x

% sudo gem install do_mysql -- --with-mysql-dir=/usr/local/mysql/ --with-mysql-config=/usr/local/mysql/bin/mysql_config 
Building native extensions.  This could take a while...
Successfully installed do_mysql-0.9.11
1 gem installed
Installing ri documentation for do_mysql-0.9.11...

Enclosing class/module 'mDO' for module Mysql not known
Installing RDoc documentation for do_mysql-0.9.11...

Enclosing class/module 'mDO' for module Mysql not known

% gem list --local | grep do_ 
do_mysql (0.9.11)
do_sqlite3 (0.9.11)

では、Windowsではどうやればいいのだろう？