<xsl:template name="SplitStringAtSeparator">
  <xsl:param name="stringToSplit"/>
  <xsl:param name="separatorCharacter" />
  <xsl:choose>
     <xsl:when test="contains($stringToSplit, $separatorCharacter)">
        <xsl:value-of select="substring-before($stringToSplit, $separatorCharacter)"/>
        <xsl:call-template name="SplitStringAtSeparator">
           <xsl:with-param name="stringToSplit"
                           select="substring-after($stringToSplit, $separatorCharacter)"/>
        </xsl:call-template>
     </xsl:when>
     <xsl:otherwise>
        <xsl:if test="$stringToSplit != ''">
           <xsl:value-of select="$stringToSplit"/>
        </xsl:if>
     </xsl:otherwise>
  </xsl:choose>
</xsl:template>

hellothisisastringtosplit

node[1] = hello
node[2] = this
node[3] = is
node[4] = a
node[5] = string
node[6] = to
node[7] = split