Here's a power-tip for you:
You said you're editing english.php ... and I bet your CUSTOM english.php contains a whole lotta stuff you did not actually customize. The tip is that you can stuff into english.php only the defines that you customized. The system will read those first, and then go read the main english.php to get all the rest!
And the side-benefit of doing that is that you don't run the risk of it trying to do all the fancy crazy includes etc that the main one does at the bottom of the file. And it sure makes upgrades a ton simpler too.
And whenever you're installing a plugin that touches english.php, WALK WITH CAUTION ... because there's no good reason for it to ever touch the english.php file at all. All the language defines for a plugin should go into the extra_definitions folder instead. So if a plugin is touching english.php then chances are it wasn't written as friendly as it should have been.