xsi:nil="true" in the response message

All,

I have a SOAP to SOAP scenario. It involves one to one field graphical mapping. Simple fields with no attributes. The problem now is that the response I am getting back for the some of the empty fields from the target system is:

- < GetDpmSubProjectPhotonViewResponse xmlns = http://ABC xmlns:soap =" http://schemas.xmlsoap.org/soap/envelope/ " xmlns:xsd =" http://www.w3.org/2001/XMLSchema " xmlns:xsi =" http://www.w3.org/2001/XMLSchema-instance " >

- < GetDpmSubProjectPhotonViewResult >

< StatusCode > 0 </ StatusCode >

< StatusMessage > Sub Project information retrieved successfully </ StatusMessage >

< SubProjectKey > dsdd </ SubProjectKey >

< Name > Safeway Horton Hears a Who Floorstand x48 (DVD Version) </ Name >

< ShipDate > 2008-11-10T00:00:00 </ ShipDate >

< DisplayQuantity > 1279 </ DisplayQuantity >

< CreativeCost xsi:nil =" true " />

< DisplayCost xsi:nil =" true " />

< CorrugateCost xsi:nil =" true " />

< PopCost xsi:nil =" true " />

< GroupYear > 2008 </ GroupYear >

< CompanyKey > 1 </ CompanyKey >

- < RetailAccountPhotonViews >

- < RetailAccountPhotonView >

< Name > SAFEWAY </ Name >

</RetailAccountPhotonView>

</RetailAccountPhotonViews>

</GetDpmSubProjectPhotonViewResult>

</GetDpmSubProjectPhotonViewResponse>

This after one to one mapping in PI becomes:

<?xml version="1.0" encoding="UTF-8" ?>

- < ns1:MT_DPMSubProjectServiceResponse xmlns:ns1 = http://xyzzz >

< Status_Code > 0 </ Status_Code >

< Status_Message > Sub Project information retrieved successfully </ Status_Message >

< Sub_Project_Key >asdds </ Sub_Project_Key >

< Sub_Project_Name > Safeway Horton Hears a Who Floorstand x48 (DVD Version) </ Sub_Project_Name >

< Sub_Project_Cycle_Ship_Date > 2008-11-10T00:00:00 </ Sub_Project_Cycle_Ship_Date >

< Sub_Project_Display_Qty > 1279 </ Sub_Project_Display_Qty >

< Sub_Project_Creative_Cost xsi:nil =" true " xmlns:xsi =" http://www.w3.org/2001/XMLSchema-instance " />

< Sub_Project_Display_Cost xsi:nil =" true " xmlns:xsi =" http://www.w3.org/2001/XMLSchema-instance " />

< Sub_Project_Corrugate_Cost xsi:nil =" true " xmlns:xsi =" http://www.w3.org/2001/XMLSchema-instance " />

< Sub_Project_POP_Cost xsi:nil =" true " xmlns:xsi =" http://www.w3.org/2001/XMLSchema-instance " />

< Group_YR > 2008 </ Group_YR >

< Company_Key > 1 </ Company_Key >

- < RetailAccountPhotonViews >

- < RetailAccountPhotonView >

< Name > SAFEWAY </ Name >

</RetailAccountPhotonView>

</RetailAccountPhotonViews>

</ns1:MT_DPMSubProjectServiceResponse>

How do we ensure that the target system does not send xsi:nil="true" in the response message and or how do I remove it in Pi with XSLT mapping.