title: Zend_Search_Lucene and range search
body: <p>I have a bunch of int key fields in my index and trying to do a simple range search like this:</p>
  
  <pre><code>`gender:1 AND height:[120 TO 180]`
  </code></pre>
  
  <p>This should give me male in the height range 120 to 180. But for some reason i get this exception:</p>
  
  <pre><code>`At least one range query boundary term must be non-empty term`
  </code></pre>
  
  <p>How would i debug this? Is it just Zend_Search_Lucene being buggy?</p>