Andrej [1] discovered utPLsql as I found utPLsql [2] some time ago... he thinks - and I guess I can agree absolutely - that refactoring pl/sql is harder than refactoring java:
1) refactoring java usually doesn't impact production data, but when refactoring sql you have to think about migrating data, which usually means creating a lot of migration scripts. {except you have some wonderful tools I am still looking for}
2) there's no tool support for pl/sql refactoring as in Java...
well... his thread has a nice discussion where even creator Steven Feuerstein put his 2 cents into it, so that's definately worth a read...