The reason why adding the Jipijapa integration jars to AS7 didn't work, is that you would also need other code changes that use the Jipijapa interfaces.
If you need a Hibernate bug fixed for your production use of AS 7, look into using JBoss EAP (product version of AS 7) which might have the Hibernate bug fixed already. Do you know a HHH jira number for the bug?
Hibernate 4.3.0 has a severe bug:
This bug is caused by this feature: [HHH-8563] javax.persistence.Query#getLockMode should throw ISE in some cases - Hibernate JIRA