Can you post a test case that replicates it and I'll take a look?

Thanks.

"mwelss" wrote:

Looking at the code, the payload seems to be serialized, but on the producer I set the delivery-mode to non-persistent, so why
serialize anyway? It's all in one jboss, no cluster etc.

http://java.sun.com/j2ee/sdk_1.3/techdocs/api/javax/jms/ObjectMessage.html

ObjectMessage::setObject javadoc:
Sets the serializable object containing this message's data. It is important to note that an ObjectMessage contains a snapshot of the object at the time setObject() is called; subsequent modifications of the object will have no effect on the ObjectMessage body.

"mwelss" wrote:
Can it be a concurrency issue? The consumers are all servlets, to which the messages are delivered almost 'at the same time'.

I have managed to replicate this.

It's a race condition due to >1 threads concurrently deserializing the message.

The fix seems to be trivial. So hopefully will be in the next release.

In the mean-time you should be able to work around by synchronizing on the underlying message as you mentioned. Although is slightly more complex since the message you have is actually a proxy.

You need to do something like:

OjbectMessage m = (ObjectMessage)consumer.receive();

MessageProxy mp = (MessageProxy)m;

JBossMessage jbm = mp.getMessage();

synchronized (mp.getMessage())
{

 Object myObject = m.getObject();
}