Record locking in postgresql

Hi,

I'm using Spring/Hibernate/GWT. In my DaoImpl I have metod getLockRecordForEdit() for that I'm using getHibernateTemplate().get(Object ... , LockMode.UPGRADE) but when I opened new web client I can edit, remove locked record why?
I checked in postgresql SELECT FOR UPDATE and when I wrote:
begin;
SELECT * .... FOR UPDATE;
record was lock because I didn't write COMMIT.
How to get and lock row from DB by spring/hibernate?
I suppose that I shouldn't use HibernateTemplate I should begin new session and transaction get record end when user finished edit record save end commit
sorry for my english.
Regards from Poland