title: Ruby: invalid byte sequence in UTF-8
body: <p>I'm writing a Django project that uses the <a href="http://lesscss.org/" rel="nofollow noreferrer">LESS</a> language.  I'm using the <a href="http://github.com/dziegler/django-css" rel="nofollow noreferrer">django-css</a> application to do this.  My colleague is getting the following error, but I am not.  I suspect that this might be because the encoding is wrong on the file being compiled.  The weird thing is that we cloned from the same hg repo so I don't see why his files' encoding would be wrong and mine right.</p>
  
  <pre><code>TemplateSyntaxError at /qa/
  Caught an exception while rendering: /home/rajoy/.gem/ruby/1.9.1/gems/less-1.2.21/lib/less/engine.rb:49:in `gsub': invalid byte sequence in UTF-8 (ArgumentError)
      from /home/rajoy/.gem/ruby/1.9.1/gems/less-1.2.21/lib/less/engine.rb:49:in `prepare'
      from /home/rajoy/.gem/ruby/1.9.1/gems/less-1.2.21/lib/less/engine.rb:30:in `parse'
      from /home/rajoy/.gem/ruby/1.9.1/gems/less-1.2.21/lib/less/engine.rb:45:in `to_css'
      from /home/rajoy/.gem/ruby/1.9.1/gems/less-1.2.21/lib/less/command.rb:58:in `parse'
      from /home/rajoy/.gem/ruby/1.9.1/gems/less-1.2.21/lib/less/command.rb:51:in `run!'
      from /home/rajoy/.gem/ruby/1.9.1/gems/less-1.2.21/bin/lessc:102:in `&lt;top (required)&gt;'
      from /var/lib/gems/1.9.1/bin/lessc:19:in `load'
      from /var/lib/gems/1.9.1/bin/lessc:19:in `&lt;main&gt;'
  </code></pre>
  
  <p>I have ruby 1.8.6 and gems 1.3.6.</p>
  
  <p>My colleague has ruby 1.8.7 and gems 1.9.1.</p>
  
  <p>What are the possible reasons for why this is happening?</p>