Why do I get "java.lang.ClassNotFoundException: javax.persistence.MapKeyColumn" while starting BRMS stanadalone server on AIX server with IBM JDK combination ?

Issue

• I have just unzipped and tried to start the JBoss Enterprise BRMS Platform 5.3 standalone installation on AIX 5.3 server, but I get the following ERROR while the server starts.

ERROR [org.jboss.kernel.plugins.dependency.AbstractKernelController] (main) Error installing to Start: name=persistence.unit:unitName=jbpm-human-task.war#org.jbpm.task state=Create
java.lang.TypeNotPresentException: Type javax.persistence.MapKeyColumn not present
    at com.ibm.oti.reflect.AnnotationHelper.getAnnotation(AnnotationHelper.java:39)
    at com.ibm.oti.reflect.AnnotationHelper.getDeclaredAnnotations(AnnotationHelper.java:51)
    at com.ibm.oti.reflect.Field.getDeclaredAnnotations(Field.java:36)
    at java.lang.reflect.Field.getDeclaredAnnotations(Field.java:1040)
    at java.lang.reflect.AccessibleObject.getAnnotations(AccessibleObject.java:187)
    at org.hibernate.cfg.annotations.reflection.EJB3OverridenAnnotationReader.getJavaAnnotations(EJB3OverridenAnnotationReader.java:2080)
        ...
Caused by: 
java.lang.ClassNotFoundException: javax.persistence.MapKeyColumn
    at java.lang.Class.forNameImpl(Native Method)
    at java.lang.Class.forName(Class.java:169)
    at com.ibm.oti.reflect.AnnotationHelper.getAnnotation(AnnotationHelper.java:34)
    ... 82 more

Just for your information, I am using IBM Java SDK 1.6.0 (SR8) . Can you please suggest me how to get rid of this ERROR?