It seems that if one wishes to use a different container than the 'hibernate' one it still ends up using the hibernate container. (AS 7.2.0.Final-redhat-8)
For example if we create a new container called 'jpa' as below and verify the cache container started up fine via logs/admin console.
<cache-container name="jpa" default-cache="local-query" start="EAGER" module="org.jboss.as.jpa.hibernate:4" jndi-name="java:jboss/infinispan/jpa">
<local-cache name="entity">
<transaction mode="NON_XA"/>
<eviction strategy="LRU" max-entries="10000"/>
<expiration lifespan="1800000"/>
</local-cache>
<local-cache name="local-query">
<transaction mode="NONE"/>
<eviction strategy="LRU" max-entries="10000"/>
<expiration max-idle="1000000"/>
</local-cache>
<local-cache name="timestamps">
<transaction mode="NONE"/>
<eviction strategy="NONE"/>
</local-cache>
</cache-container>
and add the cachemanager reference in persistence.xml for 2LC
<property name="hibernate.cache.infinispan.cachemanager" value="java:jboss/infinispan/jpa" />
<property name="hibernate.cache.region.factory_class" value="org.jboss.as.jpa.hibernate4.infinispan.InfinispanRegionFactory" />
but it still uses the hibernate container.
INFO [org.jboss.as.clustering.infinispan] (ServerService Thread Pool -- 59) JBAS010281: Started example.war#com.example.blah cache from hibernate container