Expiration of passwords

Any ideas on the best way to do this:

How can we control the use and expiration time of passwords using ORACLE as a RDBMS in a client-server architecture, using any applications such as Power Builder, Access etc.

Thanks.
Alexandre Vinhaes Barboza
Brasil - Rio de Janeiro
Phone: (021) 390-1443 Received on Tue May 28 1996 - 00:00:00 CEST