Try to define a custom transport. This should be something like that:
import xmlrpclib, httplib
class sourcedTransport(xmlrpclib.Transport):
def setSource(self, src):
self.src = src
def make_connection(self, host):
h = httplib.HTTPConnection(host, source_address= self.src)
return h
srcPort = 43040
srcAddress = ('', srcPort)
p = sourcedTransport()
p.setSource(srcAddress)
server = xmlrpclib.ServerProxy("server:port", transport=p)
EDIT: bug fix httplib.HTTP => httplib.HTTPConnection
And checked that it works, in python 2.7 (but not before)