Nothing specific to
JSF. You can probably find some samples of utility classes that overload the Properties load() method using a database as a source.
There are 2 main reasons why nothing specific to DBMS's:
First, because you can arrange the properties in the DBMS however you like and different people like different ways. There's no "one-size-fits-all" solution.
Secondly, flat files and DBMS's aren't the only ways to get properties. I could use LDAP, a web service, even the Fairy Courier Delivery Service. So rather than try for every possible specific solution, they made the Properties class extensible.
A DBMS-loaded Properties class shouldn't be too difficult. Just extend java.util.Properties and overload the load() method with one that opens the connection to the DBMS, reads the key/value pairs and does a "this.setProperty()" against each. And closes the connection when you're done, of course.