I actually spent quite a bit of time investigating this as I had a large amount >20GB stored accross various MDBs that needed consolidating and cleaning. After much headache I can give you these points.
The Sun JDBC/ODBC bridge driver is worthless.
You will need a commercial JDBC driver to do anything
Writing a dialect for access is more trouble than it's worth
If you're goingto the trouble of writing in Java, and then distributing a Java application with all the attendant headache (JRM etc.) then you may as well go the extra half inch, put a proper database in and just write something to move the data from access to a real database.
Doing anything serious with access will cause your eyeballs to bleed, if you're not doing anything serious then Hibernate is probably overkill.