Both are WordPress 2.0.1.
If you click on the "Complete Archives" link under the calendar, on the test blog it takes you to the proper page.
On the real blog it errors out.
The plug in has been installed for both (to handle the "fake 404") and neither would work until I created a page for "Complete Archives".
Contacted the author who (1) told me to read the README file (which I already had done, it didn't make it work), (2) tell me that I should not have created the page and (3) told me "You're supposed to fix the PHP in the plugin, because it *fakes* the mythical, non-existant 'archives' page."
Guys, I know less about PHP than I know what goes on under the hood of my car.
What the HECK does "fix the PHP in the plugin" mean? It finds the correct file paths, what more needs to be done?