404 Page w/setting up Custom Domain

Just tried setting up a custom domain, getting this error:

Server Error in '/' Application.
The resource cannot be found.
Description: HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable. Please review the following URL and make sure that it is spelled correctly.

Requested Url: /admin/util/changeDomain.aspx

UPDATE: Just did a hard refresh and verified the cname correctly.
UPDATE: FYI...page breaks when editing post, viewing users profile w/ Mac FF 3.0.4 -

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