title: How to permanently change a system property in TeamCity 6 from a build step
body: <p>I have found a way to change a property in TeamCity:</p>
  
  <pre><code>##teamcity[setParameter name='ddd' value='fff']
  </code></pre>
  
  <p>But unfortunately this change only occurs for the current build. I want this change to be PERMANENT, but TeamCity only changes this for the current running build.</p>
  
  <p>How do I make a permanent change to a system property in TeamCity?</p>