Via mailing lists and Al Iverson’s Spamresource blog, Yahoo China domains (yahoo.com.cn and yahoo.cn) are no longer accepting email.  Yahoo announced in April of 2013 they are shutting down their email services in August of the same year and advises users to create new accounts with Alibana.  While the domains still have valid MX records, they are no longer accepting mail.  There is no direct mapping from Yahoo China addresses to Alimail (Alibana’s email service).
When attempting to send emails to these two domains, the reject will be a “550 relaying denied” message.  Now would be a good time to update your lists and remove any yahoo.com.cn and yahoo.cn addresses.

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