EDI 856s Mapping issue - LIN03 NDC Number needs to populate 11 digit number

Question

My scenario was I'm getting input 856s file from RXTPL with 10 digit NDC Number but client wants it as 11 digit ( needs to add Zero @ center) . That's my requirement.
I implemented same thing in mapping with Scripting Functoid and even tried with functoids also but didn't get 11 digit number as output.

used inline xslt call template:
<xsl:template name="ConvertingNDCTo11DIGIT">
<xsl:param name="TenDigitNDC"/>
<xsl:variable name="FIRST5DIGITS" select="substring($TenDigitNDC,1,5)"></xsl:variable>
<xsl:variable name="Second5DIGITS" select="substring($TenDigitNDC,6,5)"></xsl:variable>
<xsl:element name="LIN03" >
<xsl:value-of select="concat($FIRST5DIGITS,'0',$Second5DIGITS)"/>
</xsl:element>
</xsl:template>

Not implemented this script simply getting 10 digit NDC Number only.
Could you please give me some suggestions .

Thanks
venkat