Could it be something like using
<xsl:attribute name="to"><xsl:value-of select="'admin@mail.com,boss@mail.com'" /></xsl:attribute>
or
<xsl:copy-of select="mail/header/@to" />
Could it be something like using
<xsl:attribute name="to"><xsl:value-of select="'admin@mail.com,boss@mail.com'" /></xsl:attribute>
or
<xsl:copy-of select="mail/header/@to" />