CNAME vs A?

[Dave Lers]

I posted a similar question w/ no reply, this is bugging me so I'm
trying again.

I know the following is correct

dalrun.com.		IN	A	24.16.244.57
www.dalrun.com.		IN	CNAME	dalrun.com.
dalrun.com.		IN	MX      5	dalrun.com.
dalrun.com.		IN	NS	dalrun.com.

but I have seen the following also claimed to be correct, nslint tells
me its not and, with one exception, I've never seen it used in the
documentation I've found, yet I also haven't seen anything that says
its a bad thing. An aye or nay with an explanation, or a pointer to
one, would be appreciated.

dalrun.com.		IN	A	24.16.244.57
www.dalrun.com.		IN	CNAME	dalrun.com.
mail.dalrun.com.		IN	A	24.16.244.57
dalrun.com.		IN	MX      5	mail.dalrun.com.
ns1.dalrun.com.		IN	A	24.16.244.57
dalrun.com.		IN	NS      	ns1.dalrun.com.

I've seen it 2x in a row now with NS records (different A records
using the same IP). With CNAME's and aliases in Apache I'm fine (and
sendmail looks doable the same way) but what about DNS ?, with a
single IP it seems I'm stuck with dalrun.com. Am I missing something,
is there an acceptable way, with a single IP, to use ns1.dalrun.com
for my NS record?

-- 
Dave Lers
http://www.BaywoodDesign.com/