When you choose a particular version of Hibernate to use witih your application (via your pom.xml), the version that you specify, is only used to compile your application code (the Hibernate version information does not get passed into the application server).  Instead the application server tries to match up the persistence provider classname that you specified in the persistence.xml, with available known persistence provider modules.  There are persistence.xml properties for hinting that a specific module be used (you don't need to set them usually but its good to know about them). 

You could try adding the newer Hibernate jars.  Have you looked at switching to AS 7.1?  We are using Hibernate 4.0.1 in AS 7.1 (which is pretty close to Hibernate 4.1). 

Switching Hibernate to a newer version could be done by:

1. Delete as7/modules/org/hibernate/main/*.index files.
2. Replace current Hibernate 4.x jars in as7/modules/org/hibernate/main with new ones.
3. Update as7/modules/org/hibernate/main/module.xml to use newer Hibernate jar names.

Scott