Empty response returned when SOAP Fault is thrown from an endpoint with WS-Security Policy Signature profile in EAP 6

Issue

• We are using WS-Policy to enforce signature requirements on our web services.
• When a service with these policies throws a fault (e.g. a business exception), the server is responding with an empty response - more specifically, a HTTP 500 response with a "Content-Length: 0" header.
• We have tested this with both Java-first and contract-first services - both behave the same way. The fault is returned as expected when WS-Policy is removed.
• We have also tried using a different policy (UsernameToken), and faults are handled as expected, so this appears to be specific to the signature policies we are using.