Hi guys,
excuse me if i open another post on the same argument but now i've
cleared my problem,so i think a new discussion can be useful. Thanks
for precedent replies.

I've to use a transaction in my jsf application.
My problem is:
User insert an experiment into db using 6 different web pages, each
page create one or more prepared statements.
I want the inserting in my db tables happens into a transaction.
I've done this.

The first bean creates an arraylist of statements,and each statements
created in the application has putted into arraylist.
At the end a queryManager loads the arraylist from the first bean,
reads it and executes the statements in a transaction.
The question is transaction doesn't work, commit and rollback doens't
work.
For better understanding the problem i've tried to create a prepared
statement directly from query manager and using transaction and it
works!!
Commit and rollback works correctly!
Why if i try to load an arraylist of statements stored in another bean
transaction doesn't work?
I'm crazying, please help me...
Can you say me another method to collect prepared statements and use it
into a transaction?