Synchronous messages through Soap Adapter

Question

Hi XI Guru's
In my scenario I am sending a synchronous soap message over soap adapter. Message flow is  like
3rd Party Application --> XI --> SAP R/3.
My message do get processed in SAP R/3 and I do get response in SXMB_MONI as well as in Message Monitoring in RWB.
The return message for message f1bdf1d0-cec5-11de-a9c0-0050569626f6(OUTBOUND) was successfully passed to the waiting "call" thread.
2009-11-11 05:27:26     Information     The message status was set to DLVD.
2009-11-11 05:27:26     Information     SOAP: response message entering the adapter (call)
2009-11-11 05:27:26     Information     SOAP: response message leaving the adapter
But still the response from XI does not reaches 3rd party application.
On digging the logs I found following message.  Can this be an issue in XI which is blocking the reponse message from reaching the 3rd Party Application.( I tried posting the message through XML spy and I do get the response in XML spy.)
(Note : My XI Installation has central adapter engine)
#1.5 #0050569626F6004200000D0B00000B5000F66675B4B8DEA5#1257401122698#com.sap.engine.services.servlets_jsp.client.RequestInfoServer#sap.com/com.sap.aii.adapter.soap.app#com.sap.engine.services.servlets_jsp.client.RequestInfoServer#LOVEIN#25369##sapnw03_NPI_6935550#Guest#2fd59d51c9d111debb440050569626f6#HTTP Worker [4]##0#0#Warning##Plain###Cannot send an HTTP error response [500 "Application error occurred during the request procession." (details: "The WebApplicationException log ID is [0050569626F6004200000D0800000B5000F66675B4B8DEA5].")]. The error is: com.sap.engine.services.servlets_jsp.server.exceptions.WebIOException: *The stream is closed.*
+     at com.sap.engine.services.servlets_jsp.server.runtime.client.ServletOutputStreamImpl.ensureOpen(ServletOutputStreamImpl.java:354)+
Any help in this regard is appreciated .
Thanks
Lovein

Answer 1

Thanks for your reply Stephan / Abhishek.
To add some more info on the issue. This issue is when I am using PI 7.1 version.
I do not face the issue if I use XI 3.0 and end to end flow works fine and response message reaches 3rd party application.
Only difference I have in 2 versions is that in XI 3.0 we have been able to disable the soap adapter authentication (by changing web.xml file) where as in PI 7.1 we have not been able to disable that authentication and userid/ password info has to be provided while sending the soap message from 3rd Party application.
(Security if not disabled gives 401 message as described on following blog [SOAP Sender ADAPTER 401 No Authorisation|SOAP Sender ADAPTER 401 No Authorisation] )
On the other note do you guys know a way to disable this authentication on PI 7.1 version.
Thanks ,
Lovein