I've pulled the latest source from git and modified the source to support hibernate 4 (see attached patch).
I also added a persistent type for DateTimeZone.
I'm not currently actively maintaining Joda-Time-Hibernate. However, I may pull in GitHub pull requests at some point in the future, so if you'd like the chance of it being included, please create a fork there and create a pull request with your patch.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Patch for Hibernate 4 support
I'm not currently actively maintaining Joda-Time-Hibernate. However, I may pull in GitHub pull requests at some point in the future, so if you'd like the chance of it being included, please create a fork there and create a pull request with your patch.