I've got a Site-wide Error handler and the missing template handler set up on the server, and the Site-wide handler does catch some errors, but not all of them. It seems to catch errors like incorrect variable names in the Coldfusion, but wouldn't catch an error returned from a MySql query, or an array entry undefined error. Instead of my error handlers it goes back to the default Coldfusion handlers.
I know the pages can be seen on the server at the correct paths as I've navigated to them manually, plus some of the errors are being caught but not all of them.
The biggest problem is that the errors not being caught are far more serious than the small ones that are.
It's Coldfusion 7 running on Red Hat.