The process is very diferrent in Jboss 2.x and 3.x.
You need Jaws only with CMP beans, and datasources are configured elsewhere anyway.
In 2.x you should look in Jboss.jcml. most options are self-explanatory, and read documentation (belive it or not, it much faster than finding answer in the forum, and much more polite than asking such an ill-defined questions.)
I'm not currently using Jboss 3.x, but as I understood there are separate config files for each DS. The examples for most major DBMS can be found in CVS.
Hope this will help, fnd good luck!
Sorry for typos. This keyboard is a bit qirky...