Siebel prefix missing on Outbound WebService XML

Hi,

I am Working on an Outbounding WebService, so I imported the WSDL on Siebel Tools and Generated my Proxy BS my IO, I then configured my hierarchy on a Custom BS using PropertySet (SetType , AddChild,...). using SOAP UI to Test, I receive the Request from siebel Succesffuly , but when delivered to EndPoint refused to XML because there is a problem with the XML's Namespaces, indeed, the EndPoint expect an XML formatted like this :

<soapenv:Envelope

xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"

xmlns:wsc="http://EndPoint/webservices/WSCont ext"

xmlns:wsb="http://EndPoint/webservices/WSBusi nessFields"

xmlns:cre="