I've got 3 classes A, B and C and 2 many to many relations between A and B and between B and C. Both are not lazy.

When I do following:
open session
load an instance of B
close session
iterate over B.getCs()

it works fine. But when I do following:
open session
load an instance of A
close session
iterate over A.getBs()
iterate over B.getCs()

an exception is thrown:
net.sf.hibernate.LazyInitializationException: Failed to lazily initialize a collection - no Session
when a try to access B.getCs()

A look at the traces shows that hibernate did not generate the SQL query to load the C objects.
Does hibernate not load the whole object tree ?
Am I doing something wrong ?

What you are doing _should_ work.

If this is Hibernate 2.1 (beta), and you are certain about this, submit the code to JIRA, and I will take a look. I did change the collection loading stuff recently ... though all my tests still pass ...

Yes, I am using 2.1beta (2 or 3)
I switched back to 2.0.3, now it is ok.
I will submit my code to JIRA ...

Thanks. Appreciated.