If you really want apache to behave like samba, then I suppose you don't mind if apache runs as root. Then it becomes rather more simple to do the sort of things you are interested in. It also becomes rather more simple to compromise your box.
If I don't run Apache, then I would have to run Samba, which runs as root anyway, and therefore makes it far more simple to compromise my box anyway. I am swapping one evil for another, overall the situation is the same.
Keep in mind the application I am thinking about is not "webserver that's trying to be a fileserver", but rather a "fileserver that just happens to use the DAV protocol". I don't see the security risks of running Apache as root as being any different to running Samba as root.
Regards, Graham --
