I’ve looked at log4jdbc (which does not support datasources), p6spy which seems to be what I am looking for but it has not been updated since 2003 which makes me nervous and lists only JBoss 3.x (we use JBoss 5), and JAMon which seems heavyweight for what I am trying to accomplish (a simple log of all SQL statements running through a JBoss application server).
I was hoping that JBoss itself would have a switch to log all the sql (as Websphere does) but I cannot find any documentation for it so that functionality might not exist.
It looks like jdbcdslog might do what you’re looking for.
http://code.google.com/p/jdbcdslog/
On the wiki page for this project there are notes on connecting it to and Oracle DataSource in JBoss.