title: Pycharm install complains about OpenJDK
body: <p>I try to install Pycharm on Ubuntu 12.04 and I have this information:</p>
  
  <pre><code>user@user:~/Pobrane/pycharm-2.5.2/bin$ sh pycharm.sh
  OpenJDK Runtime Environment (IcedTea6 1.11.1) (6b24-1.11.1-4ubuntu3)
  OpenJDK Server VM (build 20.0-b12, mixed mode)
  WARNING: You are launching the IDE using OpenJDK Java runtime.
  
           ITS KNOWN TO HAVE PERFORMANCE AND GRAPHICS ISSUES!
           SWITCH TO THE ORACLE(SUN) JDK BEFORE REPORTING PROBLEMS!
  
  NOTE:    If you have both Oracle (Sun) JDK and OpenJDK installed
           please validate either PYCHARM_JDK, JDK_HOME, or JAVA_HOME environment variable points to valid Oracle (Sun) JDK installation.
           See http://ow.ly/6TuKQ for more info on switching default JDK.
  
  Press Enter to continue.
  </code></pre>
  
  <p>What to do to work normally?</p>