EMail servers fail when domain.com is a cname alias not an IP

[hanasaki <hanasaki@hanaden.com>]

Why is it that when the default for a domain.   For example, in my case, 
hanaden.com maps to a cname, MTA's fail

ex:
hanaden.com mx IP
	... no problem
hanaden.com mx somename.domainD.org
	... email for joe@hanaden.com goes to joe@somename.domainD.org
		not
	... joe@hanaden.com

Thanks.
--
hanasaki@hanaden.com
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