title: Highcharts (highstock) plotting incorrect date on x-axis line chart
body: <p>Here I have an example of a highstock chart I have generated: <a href="http://jsfiddle.net/9gTN8/" rel="nofollow">http://jsfiddle.net/9gTN8/</a></p>
  
  <p>There are 3 data points with dates defined using the <code>Date.UTC</code> method. Despite the last date in the series being <code>2013-07-15</code>, the point is plotted in August. Likewise the other points appear to be  being plotted a month ahead of where they should be.</p>
  
  <p>I have used <code>ordinal: false</code> to allow for irregular date intervals, which is a feature of highstock.</p>
  
  <p>What is the reason for this and how can I solve it?</p>
  
  <p>Edit:</p>
  
  <p>My date in each datapoint is produced from php like so:</p>
  
  <pre><code>echo "\n[Date.UTC(" . date("Y, m, d", strtotime($date)) . "), " . $value . "]";
  </code></pre>
  
  <p>I know I could have several php <code>date()</code> functions to decrement the month myself but I'd hope there'd be a more efficient way. E.g. is it possible to replicate the javascript <code>Date.UTC</code> method in php and just output the big number (no. of milliseconds since 01/01/1970) straight off?</p>