A friend of mine just released a converter of .dbf files to PostgreSQL, under the GPL license. He writes:
This document provides a step by step instruction how to convert DBase II, DBase III+, DBase IV and (to some extent) FoxProV2 files to PostgreSQL. This solution is based on the excellent Simple DBase SQL by Michael Lecuyer.
UPDATE 2013-05-18: The link above is still valid.
Maciej Bliziński 
Quisiera saber como emigrar tablas de visual fox a postgres. Gracias
Your friend’s page unreachable now. If you have the conventer, would you provide it?
Unfortunately, I don’t have it. I’ve found a copy of this page on archive.org, but the code (zip file) is not available there.
I’ve send him an e-mail about the outage.
Just in case you may come here as I did, check this link.
http://www.tv.com.pl/stepbystep/dbasepsql/