I am searching for java orm with good osgi support. I have read hibernate however, many problems happens if this involves class loading.

Use Aries JPA, it really works will all/most JPA companies, for any tutorial see here

EclipseLink works nicely in OSGi and it is well recorded, however the Aries JPA project enables you to definitely be vendor independent and switch them out easily.

If you are using Karaf you will find already features for Aries transaction and JPA.

You can test Eclipse Link. I haven't attempted it with OSGi, however they have instructions how you can do the installation under OSGi atmosphere (here), and so i assume it will work.

I have tried personally myBatis and delay pills work well.

I am most likely a lone voice within this, but I am using Hibernate very effectively with Karaf and a variety of databases. Now, I am not to imply it had been easy, however i could document the steps I needed to decide to try use Hibernate in Karaf on my small blog If you choose to use Hibernate and encounter any issues, tell me and I'm going to be pleased to help.