Get "use a different database" installer quickstart to work with jboss AS 5

The current "use a different database" installer quickstart does not work for installer:

. Not all steps have been correctly identified or described.
. Not all changes have been automated.

I had a problem in making the db schema created, but I was able to fix it changing the h2 dialect to oracle's one in the persistence.xml present jbpm-human-task-war.war
...
I just took out the war and extracted it, found the xml, updated it and built it back..this is the fix.. but when we do it thru ant build from which source that persistence.xml is being taken?

Updating task-service/resources/META-INF/persistence.xml does not help this problem.