Ok, I am observing an "interesting" behaviour. When I point my browser to a non-existent entry i.e. http://www.w-a-s-a-b-i.com/archives/2004/04/07/this_should_return_a_404/ should return a 404 error document ... but it does not, although http://www.w-a-s-a-b-i.com/archives/2004/04/07/this_should_return_a_404/index.php will return a 404! Why is this happening?
I wrote a nice little custom 404 page, which takes "this_should_return_a_404" and uses it to do a search, if empty it will redirect to another 404 with suitable info.