Position of parent node

Hi there,

I have the following XML:
<q>
  <p>
    <a>
      <b>bla</b>
      <b>bla</b>
    </a>
  </p>
  <p>
    <a>
      <b>bla</b>
      <b>bla</b>
    </a>
  </p>
</q>

Inside the <xsl:template match="b">
I would like to do the following check:

If the position of <p> within <q> is the last one
  do thing with <b>
else
  do other with <b>

but I need help in formatting the <xsl:when test="???"> statement

Thank you for any help.

--
Athanasios Gaitatzes (gaitat@xxxxxx)
Virtual Reality Department
Foundation of the Hellenic World
254 Pireos St., Tavros 17778, Athens Greece
Tel: +30 1 483-5300 ext. 1132


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