Any file which you put in the deploy directory will be deployed by JBoss.
I am also using a similar kind of design where i build a dynamic datasource.
For the next request which comes in check whether the old datasource string and the new datasource are not equal then if they are not equal then i deploy the new datasource.
And i also sleep if i deploy the datasource for sometime . So that the new datasource is deployed. But i never change the jndi name of the datasource.
I hope this must help you.