gem install mysql problem in rails

Im getting an error with a rails app. The bundled mysql.rb driver has been removed from Rails 2.2. Please install the mysql gem and try again: gem install mysql. And when i try to do gem install mysql it still doesnt work and im getting this error. WARNING: Installing to ~/.gem since /Library/Ruby/Gems/1.8 and /usr/bin aren't both writable. WARNING: You don't have /Users/bartligthart/.gem/ruby/1.8/bin in your PATH, gem executables will not run. I also tried this but it didn't work sudo gem install mysql −− −−with−mysql−config≡/usr/local/mysql/bin/mysql_config what could i do to install mysql?