title: Making a log4j console appender use different colors for different threads
body: <p>I am tracking down some concurrency issues and it would be very helpful to have the output lines from each thread in a different color when logging to a console. I am on OS X. Could this be done using a conversion pattern to output some control codes or would it need a custom appender? Anyone know how?</p>
  
  <pre><code>2011-10-21 12:14:42,859 ["http-bio-8080"-exec-9] DEBUG ...
  2011-10-21 12:14:43,198 ["http-bio-8080"-exec-10] DEBUG ...
  </code></pre>
  
  <p>The lines for exec-9 and exec-10 should be in different colors.</p>