Java EE (Java Enterprise Edition) General Discussion

I'm having trouble with the XSLT position() function. I have the following snippet of XML:

<categories>
  <category id="6">
    <title>Alumni</title>
  </category>
  <category id="10">
    <title>Built Environment</title>
  </category>
  <category id="9">
    <title>Business</title>
  </category>
  <category id="81">
    <title>Caboolture</title>
  </category>
  <category id="41">
    <title>Corporate</title>
  </category>
  <category id="2">
    <title>Creative Industries</title>
  </category>
  <category id="61">
    <title>Cultural Precinct</title>
  </category>
  <category id="5">
    <title>Education</title>
  </category>
  <category id="7">
    <title>Engineering</title>
  </category>
  <category id="44">
    <title>Feature</title>
  </category>
  <category id="4">
    <title>Health</title>
  </category>
  <category id="43">
    <title>Humanities & Human Services</title>
  </category>
  <category id="42">
    <title>Information Technology</title>
  </category>
  <category id="8">
    <title>Law</title>
  </category>
  <category id="45">
    <title>Profile</title>
  </category>
  <category id="101">
    <title>Public</title>
  </category>
  <category id="21">
    <title>QUT Carseldine</title>
  </category>
  <category id="1">
    <title>Science</title>
  </category>
  <category id="3">
    <title>What's On</title>
  </category>
</categories>

and the following template to match each category element:

<xsl:template match="category">
  <tr>
    <td width="10" valign="top" background="graphics/mid_bracket.gif">&nbsp;</td>
    <td width="10" valign="top"><img alt="" width="10" height="15" border="0" src="/graphics/blank.gif" name="rollitem0_{position()}"/></td>
    <td width="160"><a href="/general/news-event-list.jsp?news-category-id={@id}" class="level3menu"  onMouseOut="MM_swapImgRestore()"  onMouseOver="MM_swapImage('rollitem0_{position()}','','graphics/arrow.gif',1)"><xsl:apply-templates/></a></td>
  </tr>
</xsl:template>

I would expect the position() function to return 1, 2, 3, 4...19 but it doesn't. It is returning 2, 4, 6, 8...36. Does anyone have any idea why this might be happening? Surely the position should return the position of the current element within its siblings. I can only think that it is counting blank text nodes between each category element. Sorry for the complex markup, I wanted to be sure I was giving a real-world example.

Thanks.