title: jqPlot .replot() not updating series
body: <p>This issue is so deceptively simple that I'm having trouble getting my head around what the problem is.</p>
  
  <p>I have a jqPlot line chart ("plot1") with a single series and a legend.  I've bound the .click event of an anchor on my page to call the following function:</p>
  
  <pre><code>function changeSeriesColor() {
      plot1.series[0].color = "#33ff66";
      plot1.replot();
  }
  </code></pre>
  
  <p>The event fires and calls the function without errors.  The series color on the LEGEND is updated to the new color but the LINE color is unchanged.  The jqPlot docs don't have much to say about this sort of thing (I wish there were more, and more diverse, examples) and I can't find anything on stackoverflow or anywhere else that addresses this.</p>
  
  <p>This behavior is consistent in Chrome 12.0.742.112, Firefox 6.0.2 and IE 9.0.8112.16421 so I'm pretty sure it's not some weird browser-specific quirk.</p>
  
  <p>I'm at a loss on this one.  Help?!</p>