DI Server Problem updating UDF on Invoice

Hi,

I have a UDF setup as a Date on the Title of my marketing documents.

I am trying to update the UDF through the DI Server and although I receive a response that says the update was completed the field never gets updated.

I am running SAP B1 2005 SP1 patch level 32.

This is an example of the xml I am passing to the BacthInteract function of the DI Server:-

<Envelopes>

http://schemas.xmlsoap.org/soap/envelope/">

<env:Header>

<SessionID>3E162353-1CDC-4E1B-8103-9141860BE44E</SessionID>

</env:Header>

<env:Body>

http://www.sap.com/SBO/DIS">

<BOM>

<BO>

<AdmInfo>

<Object>oInvoices</Object>

</AdmInfo>

<QueryParams>

<DocEntry>1</DocEntry>

</QueryParams>

<Documents>

<row>

<U_TCPrinted>20071102</U_TCPrinted>

</row>

</Documents>

</BO>

</BOM>

</dis:UpdateObject>

</env:Body>

</env:Envelope>

http://schemas.xmlsoap.org/soap/envelope/">

<env:Header>

<SessionID>3E162353-1CDC-4E1B-8103-9141860BE44E</SessionID>

</env:Header>

<env:Body>

http://www.sap.com/SBO/DIS">

<BOM>

<BO>

<AdmInfo>

<Object>oInvoices</Object>

</AdmInfo>

<QueryParams>

<DocEntry>2</DocEntry>

</QueryParams>

<Documents>

<row>

<U_TCPrinted>20071102</U_TCPrinted>

</row>

</Documents>

</BO>

</BOM>

</dis:UpdateObject>

</env:Body>

</env:Envelope>

</Envelopes>

Does anyone have any idea as to why this would not be working?