title: libiconv missing on OSX 10.8 installing nokogiri
body: <p>I know this has been asked before, but I'm struggling to get this working and a lot of gems depend on nokogiri unfortunately</p>
  
  <p>I'm running 10.8.2 with rvm, ruby 1.9.3</p>
  
  <p>Running the following command, obtained from various gists / stack overflow questions on the topic:
      gem install nokogiri -- --with-iconv-dir=/usr/local/Cellar/libiconv/1.13.1</p>
  
  <p>gives "libiconv is missing."</p>
  
  <p>Even though looking inside that dir shows the libiconv directories.</p>
  
  <p>How can I go about getting this working?</p>