I have tried to integrate spring data jpa + hibernate + activiti5.13.But the project can't startup with exception. This happens when hibernate version is higher then 4.1.9.Final. Version 4.1.9.Final works fine. I haven't tested all the version, but version 4.2.5.Final has the problem.
Attachment connection_bug.rar is an empty project with only project configuration. The other attachment is the log. Please use maven to build and deploy it to tomcat server. Start the project and the problem can be seen.