How to use Field mapping for custom classes in an EJB2 CMP application in EAP6

Issue

• We migrate an EJB2 application with CMP Entities to EAP6 and use the following jbosscmp-jdbc.xml mapping

  <user-type-mappings>
    <user-type-mapping>
      <java-type>custom.cmp.SimpleType</java-type>
      <mapped-type>java.lang.String</mapped-type>
      <mapper>custom.cmp.FieldMapper</mapper>
    </user-type-mapping>
  </user-type-mappings>

• After deploy a legacy EJB2 CMP application in EAP6 we see the following Exception

ERROR [org.jboss.msc.service.fail] (MSC service thread 1-7) MSC000001: Failed to start service jboss.deployment.unit."persistence.jar".component.LanguageCode.jdbc.store-manager.INIT: org.jboss.msc.service.StartException in service jboss.deployment.unit."persistence.jar".component.LanguageCode.jdbc.store-manager.INIT: JBAS010784: Failed to start JDBCStore
        ...
Caused by: java.lang.RuntimeException: JBAS010793: Could not create mapper: customer.cmp.FieldMapper
        ...
Caused by: java.lang.ClassNotFoundException: customer.cmp.FieldMapper from [Module "org.jboss.as.cmp:main" from local module loader @5b5ac942 (finder: local module finder @25533ae9 (roots: :\opt\jboss\jboss-eap-6.2.2\modules\system\layers\base\.overlays\layer-base-jboss-eap-6.2.2.CP,