If you have ever seen this in the httpd log:
[negotiation:error] ... AH00687: Negotiation: discovered file(s) matching request: /mnt/var/www/html/content/... (None could be negotiated)., referer: ...
It means that there is some conflict between file handlers in Apache. This could result in the site serving 404 errors until the cache is flushed, allowing the dispatcher handler to be able to correctly manage the content.
Check and see if mod_negotiation is being used, or if the MultiViews option has been added to the vhost. If it's removed, the dispatcher caching should function correctly.
