xalan xsl:sort does not sort!

[Stephane Dion]

Hi               I’m using Xalan and trying to sort blocks of element but without success.               I’m trying to sort each block of NetPrice element by the attribute NetAmount.  In each ProductOption, I have multiple NetPrice element               Check my example below.   Thanks for your help Stephane   <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">   <xsl:output method="xml"/>     <xsl:template match="/GetProductOptionsResponse/DetailedProduct/ProductOptionGroup/ProductOption">     <xsl:copy>        <xsl:apply-templates>          <xsl:sort data-type="number" select="NetPrice/@netAmount" order="ascending"/>        </xsl:apply-templates>     </xsl:copy>   </xsl:template>     <xsl:template match="*">     <xsl:copy>       <xsl:apply-templates/>     </xsl:copy>   </xsl:template> </xsl:stylesheet>     <GetProductOptionsResponse xmlns="http://www.org/TRIP2004A/01";>     <Header language="en" version="5.1.0"/>         <DetailedProduct availabilityStatus="available">                <ProductOptionGroup description="OPTION GROUP 1">                        <ProductOption description="option A">                <NetPrice currency="EUR" netAmount="2.27" priceReferenceID="HTLAVO13XAAX" quantity="1"/>                <NetPrice currency="EUR" netAmount="-45.09" priceReferenceID="HTLAVO13XAAX" quantity="1"/>                <TravelerPrice age="10" travelerId="003">                     <PriceSummary baseAmount="0.00"/>                </TravelerPrice>             </ProductOption>             <ProductOption description="option B">                 <NetPrice currency="EUR" netAmount="222.27" priceReferenceID="HTLAVO13XAAX" quantity="1"/>                 <NetPrice currency="EUR" netAmount="45.09" priceReferenceID="HTLAVO13XAAX" quantity="1"/>                <TravelerPrice age="10" travelerId="003">                     <PriceSummary baseAmount="0.00"/>                </TravelerPrice>             </ProductOption>         </ProductOptionGroup>         <ProductOptionGroup description="OPTION GROUP 2">                        <ProductOption description="option Z">                 <NetPrice currency="EUR" netAmount="5.55" priceReferenceID="BHTLAVO13XAAX" quantity="1"/>                 <NetPrice currency="EUR" netAmount="-145.09" priceReferenceID="BHTLAVO13XAAX" quantity="1"/>                <TravelerPrice age="99" travelerId="001">                     <PriceSummary baseAmount="1.00"/>                </TravelerPrice>             </ProductOption>         </ProductOptionGroup>         </DetailedProduct> </GetProductOptionsResponse>