Hibernate version: 2.1.7
Name and version of the database you are using: Oracle 9i

The problem is as stated in subject.
I'm using hibernate with Oracle. I must have serializable isolation for all transactions.
I must use second level cache for most classes and collections.
Isolation level must be keeped 100% serializable.

I tried to use JBoss cache but it seems that it doesnt keep 100% serializability.

How to do this in Hibernate?
Are there any ready to use solutions of this problem?
Must I write my own cache strategy?
If yes what conception is the best?