title: How do I fix Rubygems recent deprecation warning?
body: <p>I have recently run updates:</p>
  
  <pre><code>gem update --system
  gem update
  </code></pre>
  
  <p>Now, I come with a lot of deprecation warnings each time I load a gem. For example, <code>rails console</code>:</p>
  
  <pre><code>NOTE: Gem::Specification#default_executable= is deprecated with no replacement. It will be removed on or after 2011-10-01.
  Gem::Specification#default_executable= called from /Users/user/.rvm/gems/ruby-1.9.2-p180@global/specifications/rake-0.8.7.gemspec:10.
  NOTE: Gem::Specification#default_executable= is deprecated with no replacement. It will be removed on or after 2011-10-01.
  Gem::Specification#default_executable= called from /Users/user/.rvm/gems/ruby-1.9.2-p180@global/specifications/rake-0.8.7.gemspec:10.
  NOTE: Gem::Specification#default_executable= is deprecated with no replacement. It will be removed on or after 2011-10-01.
  Gem::Specification#default_executable= called from /Users/user/.rvm/gems/ruby-1.9.2p180@global/specifications/rake-0.8.7.gemspec:10.
  Loading development environment (Rails 3.0.7)
  ruby-1.9.2-p180 :001 &gt; exit
  </code></pre>
  
  <p>I use RVM, Ruby 1.9.2 and Rubygems 1.8.1. Any way to get around this problem? Revert to an older version of rubygems?</p>