The second line in the following snippet changes the marshalling for long integers to emit <i8>
instead of <int>
. Yes, it's not too pretty, but should work and fix the problem.
>>> import xmlrpclib
>>> xmlrpclib.Marshaller.dispatch[type(0L)] = lambda _, v, w: w("<value><i8>%d</i8></value>" % v)
>>> xmlrpclib.dumps((2**63-1,))
'<params>\n<param>\n<value><i8>9223372036854775807</i8></value></param>\n</params>\n'