Gem install mysql error MySQL native bindings for rub on ppc

Install went fine until the “Install MySQL native bindings for ruby”

Select which gem to install for your platform (powerpc-darwin8.0)

  1. mysql 2.7.3 (mswin32)
  2. mysql 2.7.1 (mswin32)
  3. mysql 2.7 (ruby)
  4. mysql 2.6 (ruby)
  5. Skip this gem
  6. Cancel installation

Building native extensions. This could take a while…
ERROR: While executing gem … (Gem::Installer::ExtensionBuildError)
ERROR: Failed to build gem native extension.

ruby extconf.rb install mysql – --with-mysql-dir=/usr/local/mysql
can’t find header files for ruby.