Sure.

Something like:

Properties p = new Properties();
p.load(getClass().getClassLoader().getRessourceAsStream("path in jar");

Arne

PS: Shouldn't you use the special form of properties files known
    as message bundles for this ?

....

Web start can deliver resources to applets and applications
according the the local PC and its settings (language etc.).

Yes.

URL propertyLocation = this.
   getClass().getResource("/path/to/app.properties");
System.out.println("propertyLocation: " + propertyLocation);
InputStream propertyStream = propertyLocation.openStream();

On Thu, 18 Oct 2007 22:04:59 +0300, "Willy Johnsson"
<willy.j.0@hotmail.com> wrote, quoted or indirectly quoted someone who
said :

see http://mindprod.com/jgloss/resource.html

For an example of use, see the holiday calculator which loads a text
list of holidays it supports or the In words calculator which loads a
list of languages it supports.

See http://mindprod.com/products1.html#HOLIDAYS
http://mindprod.com/products1.html#INWORDS

For customising an app to a particular language see
http://mindprod.com/jgloss/internationalisation.html
and chase the links.

Sun has special tools for customising a big app to different locales
and automatically selecting the correct customisations.