email routing to seemingly un-routeable domains

[/dev/rob0]

On Monday 2005-September-05 15:02, Jim Pazarena wrote:
> I have an issue cropping up with a domain name of:
>
>    sk.sympatico.ca
>
> a user claims that it is a valid domain name for a friend of his, but
> my mail server claims it to be un-routeable,

How so? What does it say?

> and indeed a "dig" doesn't produce much info.

It has SOA, and 2 NS records. No A nor MX.

> what happens with names such as these on mail servers which actually
> _can_ route to it? how do they do it?

Perhaps it is a case of differing views for their clients. I'm unsure 
what you are asking here. Do not confuse routing with resolution.
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