Same issue here, it worked with 5.0.c but it doesn't work anymore (I've overried it with a jar dropping it in alfresco WEB-INF/lib) and the only difference I see with the new version is that now such properties is itself inside a jar.
Anyone know a proper solution to deal with it?
By the way, I had the same issue with other overriding and all the time properties were moved into a separate jar.