I had to make 'parent_last' class loading at web module level and delete following jar files from WAR:-
geronimo-servlet_3.0_spec-1.0.jar
geronimo-javamail_1.4_spec-1.7.1.jar
stax-api-1.0.1.jar
This is because of the AssertionBuilderFactory was an implementation in 2.0.5 version of neethi.jar but is an interface in 3.0.2 which we are using due to CXF 2.7.5.
Since these jar files are automatically added at build time due to CXF dependencies, I think we'll have to manually delete these jars from WAR before deployment in WAS. Also with each deployment, we'll have to change Class Loader setting for our WAR.
To change the Class Loader order, use following path:- Enterprise Applications > MyApplicationWAR > Manage Modules > MyApplicationWAR
EDIT:
You can do the same from your POM file using <exclusions>
tag
<dependency>
<groupId>org.apache.cxf</groupId>
<artifactId>cxf-bundle-jaxrs</artifactId>
<version>${cxf.version}</version>
<exclusions>
<exclusion>
<groupId>org.apache.geronimo.specs</groupId>
<artifactId>geronimo-javamail_1.4_spec</artifactId>
</exclusion>
<exclusion>
<groupId>org.apache.geronimo.specs</groupId>
<artifactId>geronimo-servlet_3.0_spec</artifactId>
</exclusion>
</exclusions>
</dependency>
<!-- Jettison Dependency -->
<dependency>
<groupId>org.codehaus.jettison</groupId>
<artifactId>jettison</artifactId>
<version>${jettison.version}</version>
<exclusions>
<exclusion>
<groupId>stax</groupId>
<artifactId>stax-api</artifactId>
</exclusion>
</exclusions>
</dependency>