Squid dynamic access list possible?

Hi Is there a possibility to make squid to read "allowed URL" file dynamically? I have set squid so, that it reads from external text-file all the URLs, that are allowed. All other URLs are denied. I would like to have squid to read the file without "rcsquid restart". I haven't find in documentation how this could be done... Perhaps it isn't at all... Second question: How can I set up a local e-mail account so, that when mail arrives to that address, it will run an external script, that would update that text-file and put a new URL in there? Jaska.