Вместо своего кода :
<p><xsl:value-of disable-output-escaping="yes" select="item_putoff_date"/></p>
<p><xsl:value-of disable-output-escaping="yes" select="item_putend_date"/></p>
напишите:
<xsl:param name="putoff_date" select="substring-before(item_putoff_date, ' ')"/>
<xsl:param name="putend_date" select="substring-before(item_putend_date, ' ')"/>
<xsl:param name="putoff_year" select="substring($putoff_date, 1, 4)"/>
<xsl:param name="putoff_mounth" select="substring($putoff_date, 6, 2)"/>
<xsl:param name="putoff_day" select="substring($putoff_date, 9, 2)"/>
<p><xsl:value-of disable-output-escaping="yes" select="concat($putoff_day, '.', $putoff_mounth, '.', $putoff_year)"/></p>
<xsl:param name="putend_year" select="substring($putend_date, 1, 4)"/>
<xsl:param name="putend_mounth" select="substring($putend_date, 6, 2)"/>
<xsl:param name="putend_day" select="substring($putend_date, 9, 2)"/>
<p><xsl:value-of disable-output-escaping="yes" select="concat($putend_day, '.', $putend_mounth, '.', $putend_year)"/></p>