Magneto database IP is cached

[apm2006]

We have different database IP addresses for our development and production environments. Our development environment is running locally on our developer machines and pointed to a single development database server on our local network. Our production environment uses a database hosted at RackSpace and is hosted on their local network. Somehow, it appears that our development IP address has been cached on production. Here's what I have done so far:

• Verified that the IP address in app/etc/local.xml on production is correct.
• Deleted the contents of var/cache/* and var/full_page_cache/*
• Restarted our memcached servers to clear any strange caches there
• grepped our entire codebase for the dev IP address
• Dumped the mysql database and grepped the dump for the dev IP (we were desperate)
• Deleted the contents of /tmp
• Disabled custom modules

This has been working for weeks without a problem. It was when I disabled the config cache that problem started. I know what you're thinking, that it just now finally picked up a config change that someone made since the last time the cache was cleared. That makes sense. What doesn't make sense is that I've cleared every cache mentioned above, enabled the config cache using MageTool and everything works like a charm.