title: JXLS - Unsupported major.minor version 51.0
body: <p>I'm trying to use Jxls v2.2.5 to generate dynamic Excel files in my web application.
  I receive this error.</p>
  
  <pre><code>java.lang.UnsupportedClassVersionError: org/jxls/area/Area : Unsupported major.minor version 51.0
  </code></pre>
  
  <p>I'm using java 1.6 for my development. Has Jxls compiled in a later version than 1.6 ? How can I get it run in java 6?</p>