Hi,
status code 500 is DataPower default behavior in case of an error. A security measure so that it is not giving too much information to a possible attacker. If you want to return something else than error 500, create an error rule that catches the error and set error-protocol-response and error-protocol-reason-phrase variables. And remember to disable "Rewrite Error Messages" under Oracle padding attack in XML threat protection settings. An example of setting the variables in XSLT:
<dp:set-variable name="'var://service/error-protocol-response'" value="'401'" />
<dp:set-variable name="'var://service/error-protocol-reason-phrase'" value="'Unauthorized'" />
--HP
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