title: bootstrap: four span3-thumbnails in responsive span12
body: <p>We stacked a <code>span12</code>- in a <code>span8</code>-container and tried placing four thumbnails in a row. Sadly the last <code>&lt;li&gt;</code> breaks to next line although screensize would allow that all four thumbnails fit in a row.</p>
  
  <p>Same behaviour with other combinations like 6x <code>span2</code> ...</p>
  
  <p>I build a small fiddle showing this behaviour:
  <a href="http://jsfiddle.net/PnWjT/" rel="nofollow">http://jsfiddle.net/PnWjT/</a></p>
  
  <p>Any suggestions how to fix this?</p>