BizTalk XML to EDIFACT EDI assembler hitting exception - biztalk

Question

I am currently trying to convert a XML file using XSLT to a EDIFACT format file.
Translation phase seems to be fine. By using a passthru send port i am able to obtain the EDIFACT file in XML format. However, once I try to pass the file to EDISend pipeline the I am hitting the exception
Error details: "Delimiter Set could not be read from the interchange. The attribute DelimiterSetSerializedData is missing from root node"
For this particular translation I am using EdifactInterchangeXml as the target schema.
Within the XSLT itself i have also declared the following segments:
<ex0:EdifactInterchangeXml DelimiterSetSerializedData="39:-1:-1:43:58:63:42:44:-1" xmlns:ex0="http://schemas.microsoft.com/Edi/Edifact">
<!--UNB-->
<ex1:UNB xmlns:ex1="http://schemas.microsoft.com/Edi/EdifactServiceSchema">
<UNB1>
<UNB1.1><xsl:text>UNOA</xsl:text></UNB1.1>
<UNB1.2><xsl:text>1</xsl:text></UNB1.2>
</UNB1>
<UNB2>
<UNB2.1><xsl:text>PSA</xsl:text></UNB2.1>
</UNB2>
<UNB3>
<UNB3.1><xsl:value-of select="userCSharp:Mandatory(substring($Desc_COMMID,1,35))"/></UNB3.1>
</UNB3>
<UNB4>
<UNB4.1><xsl:value-of select="substring($DT,3,6)"/></UNB4.1>
<UNB4.2><xsl:value-of select="substring($DT,9,4)"/></UNB4.2>
</UNB4>
<UNB5><xsl:text>(EBP)001</xsl:text></UNB5>
<xsl:if test="$Desc_COMMID">
<UNB10><xsl:value-of select="substring($Desc_COMMID,1,35)"/></UNB10>
</xsl:if>
</ex1:UNB>
<ex2:TransactionSetGroup xmlns:ex2="http://schemas.microsoft.com/Edi/Edifact">
<ex3:TransactionSet DocType="http://schemas.microsoft.com/BizTalk/EDI/EDIFACT/2006#EFACT_1911_BAPLIE" xmlns:ex3="http://schemas.microsoft.com/Edi/Edifact">
<ns0:EFACT_1911_BAPLIE>
<!--UNH-->
<UNH>
<UNH1><xsl:text>(EBP)0001</xsl:text></UNH1>
<UNH2>
<UNH2.1><xsl:text>BAPLIE</xsl:text></UNH2.1>
<UNH2.2><xsl:text>1</xsl:text></UNH2.2>
<UNH2.3><xsl:text>911</xsl:text></UNH2.3>
<UNH2.4><xsl:text>UN</xsl:text></UNH2.4>
<UNH2.5><xsl:text>SMDG15</xsl:text></UNH2.5>
</UNH2>
</UNH>
Any suggestion what could have caused the above error?