I'm using SEAM with Ejb3 on jboss-4.0.5.GA, with SQL server 2000, driver jtds.
On one of my server i got sometimes deadlock errors :

2008-08-28 17:51:03,381 WARN [org.hibernate.util.JDBCExceptionReporter] SQL Error: 1205, SQLState: 40001
2008-08-28 17:51:03,381 ERROR [org.hibernate.util.JDBCExceptionReporter] Transaction (Process ID 53) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction.
2008-08-28 17:51:03,381 INFO [STDOUT] Exception during cancel org.hibernate.exception.LockAcquisitionException: could not execute query
2008-08-28 17:51:03,381 ERROR [STDERR] javax.persistence.PersistenceException: org.hibernate.exception.LockAcquisitionException: could not execute query
2008-08-28 17:51:03,381 ERROR [STDERR] at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:647)
2008-08-28 17:51:03,381 ERROR [STDERR] at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:73)
2008-08-28 17:51:03,381 ERROR [STDERR] at com.edieyes.optixml.ejb3.sessions.StockBean.cancel(StockBean.java:162)

The most important matter is that after it (even if i catch the Exception) my next query are all failed.

Here is my part of code failing (on about 1% of time) :

@Stateless
public class StockBean implements RemoteStock{
@PersistenceContext(unitName = "stocktest")
 protected EntityManager em;


 public void cancel(String orderNumber, String jobNumber) {
 // TODO Auto-generated method stub
 try{
 String query="SELECT c FROM StockReserved as c where c.orderNumber=?1 and c.jobNumber=?2";
 Query q = em.createQuery(query).setParameter(1, orderNumber).setParameter(2,jobNumber);

 Iterator iterator =q.getResultList().iterator();
 while(iterator.hasNext()){
 StockReserved stockReserved=(StockReserved) iterator.next();
 String oldCodeArticle=stockReserved.getCodeArticle();
 int oldQuantite=stockReserved.getQuantite();
 int status=stockReserved.getStatus();
 Stock stock=(Stock) em.createQuery("SELECT c FROM Stock c where codeArticle = ?1").setParameter(1,oldCodeArticle).getSingleResult();
 if(status==0)stock.setStockPreReserved(stock.getStockPreReserved()-oldQuantite);
 else if(status==1)stock.setStockReserved(stock.getStockReserved()-oldQuantite);

 }


 query="delete FROM StockReserved as c where c.orderNumber=?1 and c.jobNumber=?2";
 q = em.createQuery(query).setParameter(1, orderNumber).setParameter(2,jobNumber);
 int deleted = q.executeUpdate();
 System.out.println(deleted+" JOBS DELETED ");

 /////*****IT FAILS HERE

 updateJobNumbers(orderNumber,jobNumber);


 }catch(Exception e){

 System.out.println("Exception during cancel "+e.getMessage());


 e.printStackTrace();
 }
 }

}

It's Called like that

stockService.cancel("000021","001");

The best should be not to have anymore this error... but all the tried I did failed.. so if you have a solution?

Else I would like to have a way to go threw that and that the next query won't fail, because for now i have this Exception :

javax.persistence.TransactionRequiredException: EntityManager must be access within a transaction
2008-08-27 14:52:16,488 ERROR [STDERR] javax.ejb.EJBTransactionRolledbackException: javax.persistence.TransactionRequiredException: EntityManager must be access within a transaction
2008-08-27 14:52:16,488 ERROR [STDERR] at org.jboss.ejb3.tx.Ejb3TxPolicy.handleInCallerTx(Ejb3TxPolicy.java:93)

or this one

2008-08-28 17:51:03,490 WARN [org.hibernate.util.JDBCExceptionReporter] SQL Error: 0, SQLState: null
2008-08-28 17:51:03,490 ERROR [org.hibernate.util.JDBCExceptionReporter] Transaction is not active: tx=TransactionImpl:XidImpl[FormatId=257, GlobalId=SVR-EDIEYES/553168, BranchQual=, localId=553168]; - nested throwable: (javax.resource.ResourceException: Transaction is not active: tx=TransactionImpl:XidImpl[FormatId=257, GlobalId=SVR-EDIEYES/553168, BranchQual=, localId=553168])
2008-08-28 17:51:03,490 INFO [STDOUT] getSupplementsGridsPriceByFabArea org.hibernate.exception.GenericJDBCException: Cannot open connection

THANKS FOR YOUR HELP