1) MysqlDS should be MySqlDS (because that's what you have set in the -ds.xml). It is case sensitive.
2) By default the datasource is bound to java: namespace, so your jta-data-source element should be:
thank you Jaikiran Pai, in fact, I should use a <non-jta-data-source> too.
If you have any document about how the namespaces that could be used and in which cases... it would be helpful, just in case..
I'm sorry for using your post, but I have your same configuration (even if I'm using Spring 3.0.5) and I didn't succeed to make it work with jboss 5/6. I have resolved the datasource's problem but now it's like there are two autodetections of the annotated entities classes. In the first the entities are found and bounded, in the second not so any queries failed for entity "not mapped". Do you have a similar problem?