This issue is a JBoss7.1 issue and this is the JBoss version WFA2.1 is using. I can give you a solution but I need to know how are you calling the SOAP request because not all client throw this error. Example: Using a soapUI4.1 I don't get this error. I have tried with linux curl cli and that too doesn't give any errors. But calling it from Powershell script using New-WebServiceProxy throws this error.
So the solution depends on what is the client that you are using.
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