Service configuration using properties

[Roll, Kevin]

My apologies if this is documented... I've been searching and haven't been able 
to find it.

I want to configure a service using properties, for example:

@Properties({
        @Property(name = "scheduler.expression",
                value = "${some.property.scheduler.expression}"),
        @Property(name = "scheduler.concurrent", boolValue = false)
})

Is this possible? If so, where would I place the property file? For our 
purposes it would be sufficient to configure this at build time. It would also 
be nice to read other properties within the class. I'm also looking at the OSGi 
dynamic configuration stuff, but I think that is more than we need right now.

Thanks!