Need information about "Siebel Quote" Inbound Web Service

 Hi All,  
Customer is using "Siebel Quote" Inbound Web Service, QuoteInsertOrUpdate method to delete line items existing in the Quote but it does not work.

Test Case:

1-) Activate the OOB "Siebel Quote" Inbound Web Service.  
2-) Generate the WSDL.  
3-) Load the WSDL in a tool like SOAPUI.  
4-) Create a quote through Siebel App with two lines on it.
5-) Send the following request


    <asi:SiebelQuoteInsertOrUpdate_Input>
        <quot:ListOfQuoteInterface>
           <quot:Quote operation="InsertOrUpdate" searchspec="">
              <quot:Id>1-3TV2JV</quot:Id>
              <quot:ListOfLineItems>
                 <quot:LineItems operation="Delete">
                 <quot:LineItemId>1-3TWAM5</quot:LineItemId>
                 </quot:LineItems>
              </quot:ListOfLineItems>
           </quot:Quote>