So one day I wake up to a phone call from a client saying their website was broken. After looking into it, I was able to determine that the website itself was working fine, however there were now red error messages showing up on almost every page. After further looking, they were not really errors, they were PHP notices. The notices sprung up during server upgrades that migrated from PHP 5.2 to PHP 5.3. At the time, we ended up just changing the PHP error setting to no longer display notices, and the crises was averted. however looking back now we could have done it this way.