In Java How do I set my SOAP version in javax.xml.soap.SOAPConnection

In Java How do I set my SOAP version in javax.xml.soap.SOAPConnection

In this code .. I need to specify Soap Version 1.1 How do I do that:
" SOAPConnectionFactory soapConnectionFactory =
SOAPConnectionFactory.newInstance(); SOAPConnection soapConnection =
soapConnectionFactory.createConnection(); "
Thanks