I looked this note and saw similar code, however there is a lot of functionality implemented in kernel so I can’t tell if this is that case.
Meanwhile I needed to decide if the message from SAP PI is valid or no. Unfortunately did not find any tools what can handle used canonalization method. So I made some lines of java code to verify this xml. According this seems the signature in XML produced from PI valid.
To make system work correctly I temporary made changes in ABAP where I took base64 variable with soap xml and changed some characters in body (according http://www.w3.org/TR/2001/REC-xml-c14n-20010315 , chapter 3.4). After this, the signature is correctly calculated.
So now I have a time to raise oss message and will see (I will keep inform in this thread). Thanks for care Martin.
Regards.