title: RVM can't switch to Ruby 1.9.1
body: <p>I installed Ruby 1.8.7 through apt-get. I then installed 1.9.1 through RVM.</p>
  
  <p>The RVM 1.9.1 installation was successful:</p>
  
  <pre><code>root: rvm install 1.9.1
  &lt;i&gt;Installing Ruby from source to: /usr/local/rvm/rubies/ruby-1.9.1-p378 &lt;/i&gt;
  &lt;i&gt;/usr/local/rvm/src/ruby-1.9.1-p378 has already been extracted. &lt;/i&gt;
  &lt;i&gt;Configuring ruby-1.9.1-p378, this may take a while depending on your cpu(s)... &lt;/i&gt;
  &lt;i&gt;Compiling ruby-1.9.1-p378, this may take a while, depending on your cpu(s)... &lt;/i&gt;
  &lt;i&gt;Installing ruby-1.9.1-p378 &lt;/i&gt;
  &lt;i&gt;Installation of ruby-1.9.1-p378 is complete. &lt;/i&gt;
  &lt;i&gt;Updating rubygems for /usr/local/rvm/gems/ruby-1.9.1-p378@global &lt;/i&gt;
  &lt;i&gt;Updating rubygems for /usr/local/rvm/gems/ruby-1.9.1-p378 &lt;/i&gt;
  &lt;i&gt;adjusting shebangs for ruby-1.9.1-p378 (gem irb erb ri rdoc testrb rake). &lt;/i&gt;
  &lt;i&gt;Installing gems for ruby-1.9.1-p378 (rdoc rake). &lt;/i&gt;
  &lt;i&gt;Installing rdoc to /usr/local/rvm/gems/ruby-1.9.1-p378@global &lt;/i&gt;
  &lt;i&gt;Installing rdoc to /usr/local/rvm/gems/ruby-1.9.1-p378 &lt;/i&gt;
  &lt;i&gt;Installing rake to /usr/local/rvm/gems/ruby-1.9.1-p378@global &lt;/i&gt;
  &lt;i&gt;Installing rake to /usr/local/rvm/gems/ruby-1.9.1-p378 &lt;/i&gt;
  &lt;i&gt;Installation of gems for ruby-1.9.1-p378 is complete. &lt;/i&gt;
  </code></pre>
  
  <p>However, I cannot get RVM to switch to the new version:</p>
  
  <pre><code>root: ruby -v
  ruby 1.8.7 (2008-08-11 patchlevel 72) [x86_64-linux]
  
  root: rvm 1.9.1
  
  root: ruby -v
  ruby 1.8.7 (2008-08-11 patchlevel 72) [x86_64-linux]
  </code></pre>
  
  <p>Despite that, it seems to have installed fine:</p>
  
  <pre><code>root: /usr/local/rvm/bin/ruby-1.9.1-p378 -v
  ruby 1.9.1p378 (2010-01-10 revision 26273) [x86_64-linux]
  </code></pre>
  
  <p>I also tried setting the <strong>rvm --default</strong> to 1.9.1 but that did not help.</p>
  
  <p>Why can't RVM switch to the new version? Should I just set an alias for ruby=1.9.1?</p>
  
  <p>*running Debian</p>