SOAP Receiver adapter with attachments not working

Hello,

I have a simple synchronous scenario like this; ABAP proxy with attachments to SOAP with attachments.

The SOAP receiver adapter has been configured with the parameters 'Do not Use SOAP envelope' and 'Keep attachments'. We create our own SOAP envelope with custom SOAP headers, so that's the reason for the 'Do not use SOAP envelope' setting.

When we test the scenario with an attachment then we get a timeout from PI. However, when we test the same scenario without any attachment then no errors occur.

The external webservice has also been tested with SOAP UI and it works fine.

Do you have any clues what the problem can be? What are we still missing in the configuration?

We did try with the adapter modules such as PayloadSwapBean and the Message TransformBean, so far without success...

Many thanks.

Roberto