Can somebody help me with this please...

I have an xml file along the lines of

<results>
    <result status="Pass">
      <person name="Fred"/>
      <subject name="English" />
    </result>
    <result status="Pass">
      <person name="Harry"/>
      <subject name="Maths" />
    </result>
    <result status="Fail">
      <person name="Fred"/>
      <subject name="History" />
    </result>
    <result status="Fail">
      <person name="Harry"/>
      <subject name="English" />
    </result>
    <result status="Pass">
      <person name="Fred"/>
      <subject name="Maths" />
    </result>
    <result status="Pass">
      <person name="Harry"/>
      <subject name="History" />
    </result>
</results>

And need to generate html for all result staus="Passes" sorted and displayed
like this:

Passes:
Name Subject
------ --------
Fred   English
-         Maths
Harry History
-         Maths

My best attempt so far is:

...
<xsl:for-each select="results/result[@status='Pass']">
  <xsl:sort select="person/@name"/>
  <tr>
    <td>
      <xsl:value-of select="person/@name"/>
      <xsl:value-of select="subject/@name"/>
    </td>
   </tr>
</xsl:for-each>
...

Which gives:

Passes:
Name Subject
------ --------
Fred   English
Fred   Maths
Harry History
Harry  Maths

The problems as I see it are that the output is a sub-set af the whole data,
and it is sorted.

Any ideas on how to remove the duplicate entries in the first column would
be very welcome.

-- 
Matt