Yahoo API credentials with accept header "application/xml" fails

Realm : mercury

1.Create yahoo API credentials content-type as "application/xml"

{
"onBehalfOfAccountId" : "yTMCt-rZDE-h0Ldu-w24f",
"onBehalfOfPassword" : "TSATrialYahoo55",
"accountId" : 586827
}

2.Add header as "application/xml" in Accept

3.Send a request.

Actual result:

It doesn't update the password.

HTTP/1.1 500 Internal Server Error
Server: Apache-Coyote/1.1
Content-Type: text/plain;charset=UTF-8
Transfer-Encoding: chunked
Date: Thu, 12 May 2016 15:01:29 GMT
Connection: close

JAXBException occurred : 1 counts of IllegalAnnotationExceptions. \

Snippet of tomcat log :

{Detailed log attached}

----------------------------
ID: 58
Response-Code: 200
Encoding: ISO-8859-1
Content-Type: application/json
Headers:

{content-type=[application/json], Date=[Thu, 12 May 2016 15:07:36 GMT], Server=[Apache-Coyote/1.1], Set-Cookie=[JSESSIONID=708D69A4818582188D81502FAC2056CE; Path=/distribution], transfer-encoding=[chunked]}

Payload: {"credentials":

{"YJ_ON_BEHALF_OF_PASSWORD":"qCQNLQ7KNod6Uqhvy+Q63mB9zzDHb80m7sQws0+N62GOWezuM2yTkYsz/0jNZQZ383Cvi6U+E5gvyVGZohSe1CWdw/cv9SsVU2KmkTevCud/4njrveT5zLLbrvJi2nTzlBR8L0I2fo9ZCFF4zDBUaIsh9Y0voNxYjmFy4JLcydxWef5DaJ8bsJ5g2zaxzdEeDUJ1EOujIH9Qu5VoS66nlqSfR+BPA0aM/dIJOVcUTodIpSml1zACmEOPZ1OMkMm1n9GSKkN89qa1vZ3wzkp8ZGN9aQxF8AufaNmjrdKcVA3rCVpr0fY1ldQXk/uTXDscTS+03cubMtu/ZksWu8XPzg==","YJ_ON_BEHALF_OF_ACCOUNT_ID":"yTMCt-rZDE-h0Ldu-w24f","YJ_CREDENTIALS_HASH":"2e17f7a60802f065ec3e9c20d6823587","YJ_ACCOUNT_ID":"586827"}

,"resellerId":"71b59a1a-87f5-46e9-b1b7-20f08b083f8e","merchantId":"1f2e1716-7124-4ec6-94b6-792abf8c0673","distributionId":"c8bcf22f-7c61-4acb-a5e3-341ee8367129"}
--------------------------------------
2016-05-12 15:07:36 WARN AbstractJAXBProvider:689 - com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 1 counts of IllegalAnnotationExceptions
Property theMessage appears in @XmlType.propOrder, but no such property exists. Maybe you meant null?
this problem is related to the following location:
at com.admaxlocal.external.ResponseMessage

at com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException$Builder.check(IllegalAnnotationsException.java:91)
at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getTypeInfoSet(JAXBContextImpl.java:435)
at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.<init>(JAXBContextImpl.java:276)
at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl$JAXBContextBuilder.build(JAXBContextImpl.java:1099)
at com.sun.xml.internal.bind.v2.ContextFactory.createContext(ContextFactory.java:143)
at com.sun.xml.internal.bind.v2.ContextFactory.createContext(ContextFactory.java:110)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

.
.
.
Caused by: com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 1 counts of IllegalAnnotationExceptions
Property theMessage appears in @XmlType.propOrder, but no such property exists. Maybe you meant null?
this problem is related to the following location:
at com.admaxlocal.external.ResponseMessage

at com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException$Builder.check(IllegalAnnotationsException.java:91)
at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getTypeInfoSet(JAXBContextImpl.java:435)
at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.<init>(JAXBContextImpl.java:276)
at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl$JAXBContextBuilder.build(JAXBContextImpl.java:1099)
at com.sun.xml.internal.bind.v2.ContextFactory.createContext(ContextFactory.java:143)
at com.sun.xml.internal.bind.v2.ContextFactory.createContext(ContextFactory.java:110)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

Expected Result:

Yahoo api credentials should update the password and shows in xml format.