> [JWallis]
> <td>
>       <xsl:variable name="month">OCT</xsl:variable>
>                 <xsl:choose>
>                         <xsl:when test="$month=JAN">01</xsl:when>
> <!-- etc. -->

You're missing quotes around the strings, e.g.:

	<xsl:when test="$month='JAN'">01</xsl:when>

Cheers,

	-- Paul

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