wordpress - Trouble directing A name and subdomain to different hosts

I am hosting a domain on namecheap with namecheap's DNS service.

I want to point digest.politihacks.com to politihacks.wordpress.com with a CNAME record. This works fine.

However, I also want to point the top level name politihacks.com to github's static page hosting service at 204.232.175.78. When I add the A record for this, it works as expected BUT the previous CNAME now also redirects to github instead of wordpress.

In my terminal I typed dig digest.politihacks.com and it looks like it SHOULD point to wordpress:

 ; <<>> DiG 9.7.6-P1 <<>> digest.politihacks.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 39614

;; flags: qr rd ra; QUERY: 1, ANSWER: 8, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;digest.politihacks.com.        IN  A

;; ANSWER SECTION:
digest.politihacks.com. 77  IN  CNAME   politihacks.wordpress.com.
politihacks.wordpress.com. 3533 IN  CNAME   lb.wordpress.com.
lb.wordpress.com.   17  IN  A   66.155.9.238
lb.wordpress.com.   17  IN  A   76.74.254.120

lb.wordpress.com.   17  IN  A   72.233.2.58
lb.wordpress.com.   17  IN  A   72.233.69.6
lb.wordpress.com.   17  IN  A   76.74.254.123
lb.wordpress.com.   17  IN  A   66.155.11.238

;; Query time: 43 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Thu Feb 28 02:02:18 2013
;; MSG SIZE  rcvd: 189

But as I mentioned, visiting digest.politihacks.com in my browser redirects to my github static page. What could be wrong?

Thanks!

Answer

This is not a DNS problem (although there is one problem: I get "... has no A record" instead of 204.232.175.78).

What you observe with digest is caused by a http redirect (301 Moved permanently).