This might be deliberate but $id is not defined in dvws/vulnerabilities/wsdlenum/functions.php if a username is passed that isn't in the $details array.
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<b>Notice</b>: Undefined variable: id in <b>/var/sites/dvws/secure/htdocs/dvws/vulnerabilities/wsdlenum/functions.php</b> on line <b>36</b><br />
<?xml version="1.0" encoding="ISO-8859-1"?><SOAP-ENV:Envelope SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"><SOAP-ENV:Body><ns1:check_user_idResponse xmlns:ns1="http://schemas.xmlsoap.org/soap/envelope/"><return xsi:nil="true" xsi:type="xsd:string"/></ns1:check_user_idResponse></SOAP-ENV:Body></SOAP-ENV:Envelope>