This might be considered a continuation of this question.

If I output HTML after my 404 header, It displays properly in IE and FF unless the user has Google bar instaled. If I try

header('HTTP/1.x 404 Not Found');
header("Location: http://www.example.com/?content=404_error");
die();

then I'm getting 302 from the redirect. It seems to overrule the 404

Supposedly if your output is larger than 512 bytes, the toolbar isn't supposed to override the page, but It seems to do it anyway.

I found a setting in Google's Toolbar that said "Provide suggestions on navigation errors". Turning that off provides me with the behaviour I want my visitors to experience. Does anyone know if Google provides a way for a developer to over-ride that setting for all visitors?