CNAME to S3 not working

amazon s3cname-record

I have set up a CNAME record to point to an S3 bucket. It's been up for 4 days, and the results of a DIG Lookup show that it is in place:

;; QUESTION SECTION:
;railroad.odehengineers.com.    IN  A

;; ANSWER SECTION:
railroad.odehengineers.com. 3600 IN CNAME   railroad.odeh.s3.amazonaws.com.
railroad.odeh.s3.amazonaws.com. 60 IN   CNAME   s3-directional-w.amazonaws.com.
s3-directional-w.amazonaws.com. 3613 IN CNAME   s3-1-w.amazonaws.com.
s3-1-w.amazonaws.com.   60  IN  A   72.21.203.149

I created a test page test.html which should be visible from both:

But only the first, direct URL works. The other gives a 404.

Any thoughts? Do I need to coordinate at all with Amazon? Or am I just misunderstanding the purpose of a CNAME record?