Question

It looks like the xsl:variables are not defined in the predicates in libxml2.
Is it possible or I miss something ? If I use the variable out of the predicate, then its fine.

    <xsl:variable name="smallcase" select="'abcdefghijklmnopqrstuvwxyz'" />
    <xsl:variable name="uppercase" select="'ABCDEFGHIJKLMNOPQRSTUVWXYZ'" />

   <xsl:template match="*[translate( name(), $uppercase, $smallcase ) = 'receipt']"> 
      <xsl:apply-templates select="Process"/>
      <xsl:apply-templates select="Encode"/> 
    </xsl:template>

Answer 1

Yes in XSLT 1.0, you cannot use variables inside the match attribute but I believe in XSLT 2.0 you can.

Maybe you can do something like this instead: (note that this may not work for you as-is, it depends on how the rest of your XSL is written)

<xsl:template match="*">
    <xsl:choose>
        <xsl:when test="translate( name(.), $uppercase, $smallcase ) = 'receipt'">
            <xsl:apply-templates select="Process"/>
            <xsl:apply-templates select="Encode"/>
        </xsl:when>
        <xsl:otherwise>
            <!-- do whatever else should be done -->
        </xsl:otherwise>
    </xsl:choose>
</xsl:template>