FastInfoset library is missing from EAP 6 distribution

Issue

I'm trying to configure CXF to use Fast Infoset. After configured, I get an exception like this:

JBWEB000236: Servlet.service() for servlet com.redhat.gss.ws.TestServlet threw exception: 
java.lang.ClassNotFoundException: com.sun.xml.fastinfoset.stax.StAXDocumentSerializer ...
    at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:213) 
    at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:459) 
    at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:408) 
    at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:389) 
    at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:134) 
    at org.apache.cxf.interceptor.FIStaxOutInterceptor.getOutput(FIStaxOutInterceptor.java:152) 
    at org.apache.cxf.interceptor.FIStaxOutInterceptor.handleMessage(FIStaxOutInterceptor.java:116) 
    at org.apache.cxf.phase.PhaseInterceptorChain.doIntercept(PhaseInterceptorChain.java:272) 
    ...

How can I get it working?