Format-number problem

Hi

My XML data contains an element whose contents represent a date in YYYYMMDD
format. I'm trying to get this to produce YYYY/MM/DD in the output. I've tried

<xsl:value-of
select="format-number(//E1EDK03[IDDAT='012']/DATUM,'####/##/##')"/>

where DATUM contains 20050115 but I get "20050115//" in the output. I'm
obviously misunderstanding how to use format-number. Am I trying the right
approach here?

Regards
Roger


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