Cache issue

Hi everybody!
I'm looking for a solution that I not found in the documentation. The question is:
for requests from internal ip : if you remove the file you will get 404 immediately (and if you update the file you will see the change immediately)
for requests from other ip's: if you remove (or change) the file you will be served with the original file for 15 minutes (or whatever the cache expiry time is)

Exist a solution to fix it?
Thanks in advance.
Geppo