We have Hibernate 3.3.1 with Websphere 6.1 - EJB3 feature pack.
There are Stateless session beans injected with Entitymanager with Hibernate as the JPA provider. While using @Tablegenerator with GenerationType.TABLE strategy, Hibernate throws UnsupportedException - Cannot perform isolated work.

The transaction manager lookup class used id WebsphereExtendedJTATransactionLookup with CMTTransactionFactory. It appears that the Isolater.java tries to suspend the transaction while generating primary keys which is not supported by Websphere app server.

Has any one come across this scenario before ? Please provide your thoughts as we have been stuck with this issue for quite some time.

You mention that the the transaction is suspended.
How do you declare the @TransactionAttribute annotation (if at all) after the @Stateless annotation on the concerning Entity Bean?

Sorry for the late reply.
The @TransactionAttribute annotation for this specific bean method is - @TransactionAttribute(TransactionAttributeType.REQUIRED).

and for the Entity, here is how we have provided the table generator :

@Id
@Column(name="id")
@TableGenerator(
name="TEST_ID_GEN",//Name to be used in column annotation
table="ID_GEN",//Name of the table @ db used for id generation
pkColumnName = "TBL_ID_NM",//Column of ID_GEN table
valueColumnName = "TBL_ID_CUR_VAL",//Column to store the current value
pkColumnValue="id",//The column name for which is has to be generated
allocationSize=1
)
@GeneratedValue(generator="TEST_ID_GEN",strategy=GenerationType.TABLE)
private int id;

If any one has valuble clues on this please provide your comments.

Should I repost this to some other forum :(. No response recieved as yet ...