I created a minimal app to reproduce the problem, attached.

Compile, deploy to tomcat, then create a record in the User table, or just execute:

curl -X POST http://localhost:8080/test/user/1

To create an empty user.

You can then access urls:

http://localhost:8080/test/delete1/1
http://localhost:8080/test/delete2/1
http://localhost:8080/test/delete3/1
http://localhost:8080/test/delete4/1

to execute corresponding methods in the TestController class.
Method 4 runs ok always.
Methods 1 to 3 fails with hibernate 4.2.2+, including 4.3 betas while they work fine with version 4.2.1