Some errors related to the duplicate id when mixing jstl with jsf have been fixed in the main project, they need to be backported to Mojarra 2.2.x

https://java.net/jira/browse/JAVASERVERFACES-4240 Duplicate ID exception when using composite component with c:if
https://java.net/jira/browse/JAVASERVERFACES-4072 Error Component already found when using c:if in composite components
https://java.net/jira/browse/JAVASERVERFACES-3978 Using c:if: Component ID * has already been found in the view
https://java.net/jira/browse/JAVASERVERFACES-3940 Dynamic <ui:include> duplicates a composite component
https://java.net/jira/browse/JAVASERVERFACES-4204 Dynamic Composite Component in ui:include lead to duplicate id Exception