Version 1.5 user-guide says:

Note: The Database classes can not be extended or replaced with your own classes, nor can the main Controller class. All other classes are able to be replaced/extended.

The Loader class cannot be extended as well. (Edit: some BS was here :P )

Edit: issue only addresses PHP4

*sry bout doublepost*

Ah, yes. I have located the error.

In PHP 4, the loader class is loaded at a early state, so the base class can extend it. And that is where the problem lies.

It will always load the core library.

I cannot see any easy solution though. I’ll leave that to Rick