Here are the logs for a request which doesn't return anything, and a request which returns the expected.
aw_api_lib.log
[04 Mar 2015 14:53:07,766 - INFO ] auth=OAuth client_id= service=ManagedCustomerService method=get response_time=287 request_id=00051076c55f2a980adb476ad3005763 operations=1 is_fault=no
[04 Mar 2015 15:04:48,601 - INFO ] auth=OAuth client_id= service=ManagedCustomerService method=get response_time=265 request_id=00051076ef21ac210adb476ad3005763 operations=1 is_fault=no
soap_xml.log
[04 Mar 2015 14:53:07,022 - INFO ] Outgoing Request:
[04 Mar 2015 14:53:07,717 - INFO ] Incoming response:
[04 Mar 2015 15:04:46,735 - INFO ] Outgoing Request:
[04 Mar 2015 15:04:48,420 - INFO ] Incoming response: