Posible duplicado:
Postgres - la última versión 0.14.0 de la gema "pg" da error

Soy nuevo en los rieles. Quiero usar PostgreSQL ya que Heroku lo usa también, pero me está costando mucho instalar elpg joya. Aparentemente, faltan algunos archivos y no se puede crear un Makefile.

Mi archivo de gemas se ve así:

source 'https://rubygems.org'

gem 'rails', '3.2.6'
gem 'faker', '1.0.1'
gem 'pg', '0.12.2'
gem 'json'

group :development, :test do
  gem 'rspec-rails', '2.10.0'
end

group :assets do
  gem 'sass-rails',   '~> 3.2.3'
  gem 'coffee-rails', '~> 3.2.1'
  gem 'uglifier', '>= 1.0.3'
end

gem 'jquery-rails', '2.0.0'

group :test do
  gem 'capybara', '1.1.2'
  gem 'factory_girl_rails', '1.4.0'
end

Y cuando corrobundle install Me sale el siguiente error al instalar la gema pg:

    Installing pg (0.14.0) with native extensions 
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb 
checking for pg_config... yes
Using config values from /usr/local/bin/pg_config
checking for libpq-fe.h... yes
checking for libpq/libpq-fs.h... yes
checking for pg_config_manual.h... yes
checking for PQconnectdb() in -lpq... no
checking for PQconnectdb() in -llibpq... no
checking for PQconnectdb() in -lms/libpq... no
Can't find the PostgreSQL client library (libpq)
*** 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=/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby
    --with-pg
    --without-pg
    --with-pg-dir
    --without-pg-dir
    --with-pg-include
    --without-pg-include=${pg-dir}/include
    --with-pg-lib
    --without-pg-lib=${pg-dir}/lib
    --with-pg-config
    --without-pg-config
    --with-pg_config
    --without-pg_config
    --with-pqlib
    --without-pqlib
    --with-libpqlib
    --without-libpqlib
    --with-ms/libpqlib
    --without-ms/libpqlib


Gem files will remain installed in /Users/KennyGWang/.bundler/tmp/18833/gems/pg-0.14.0 for inspection.
Results logged to /Users/KennyGWang/.bundler/tmp/18833/gems/pg-0.14.0/ext/gem_make.out
An error occured while installing pg (0.14.0), and Bundler cannot continue.
Make sure that `gem install pg -v '0.14.0'` succeeds before bundling.

Instalé postgresql usando homebrew,brew install postgresqlasíwhich psql me da/usr/local/bin/psql

Cualquier ayuda es apreciada!