XLST 'DISTINCT' Equivalent

Hi,

I was wondering if there was a way of using XSLT to return a distinct set of
values from an XML document?

e.g.

<TAG1>
  <TAG2>John</TAG2>
  <TAG2>Fred</TAG2>
  <TAG2>John</TAG2>
</TAG>


What I want back using XSL or XSLT is Fred and John.

James :-)