I would definitely be interested in hearing any responses to this question.
I have recently been doing some research on some legacy Struts applications (version 1.1 - if one would consider that old enough to consider it "legacy"), and the book I am reading makes mention of different database pooling drivers. It mentions DBCP. However, the Hibernate book (which was just released) I have been reading mentions C3P0. The company I work for currently works on a database connection pooling package that was developed by the developers who initially developed the original framework.
I am wondering these questions out of my own curiosity and any input anyone might be able to provide would greatly be appreciated. Also, the link leading to the hibernate forums above is broken.