[Zope] Customizing Error pages?

In response to Paul Winkler (because I'm no good with mailing lists). I've tried modifying standard_error_message, and it seems like it works sometimes. My impression of it is that standard_error message picks up Zope Errors, but there is some other template somewhere which picks up Site Errors. Interestingly enough, the Site Errors template will attempt, to a degree, to make use of the standard_error_message. I guess I will do some searching and see if a solution to this pops up. Thanks, Alec