Cannot make http call during JCO thread

Question

The software makes a call as follows:
1. EJB via JCO calls a remote enabled function on an R3 server.
2. The function calls a class with some information that is posted as XML using if_http_client.
3. A rest service on another server recieves this as an HTTP post.
The same software is called from an SAP GUI process which calls the same class method that makes the http call.
Errors only occur when the http call attempt is made during the RFC process through the JCO call from java.
No error occurs when called during a users activity in an SAP GUI screen.
Also, this error does not occur on our dev or test systems. The error only occurs in production.
ERROR DETAILS:
during http_client->send we get an http_communication_failure.
Tracing shows that the actual error is: HTTPIO_PLG_ICM_CONNECT_FAILED which is deep in the code during the actual system call by the sap software.
We have traced through logs, and checked all kinds of settings. Our test system is a photocopy of our production system, including user settings.
Any Ideas?

Answer 1

There doesn't seem to be anything in your question that relates to the usage of Web Dynpro ABAP.  Perhaps you would find a better response in another forum that more closely matches the technologies you are dealing with.