[exim] Broken DNS entries not allowed

Hi, all.
Is there a way to make exim send email to an address that has a broken
dns entry?

Sending email to unifrax.cn results in this:

2007-01-12 09:54:30 1H5Oje-0007he-BJ ** ygao@???: all relevant MX
records point to non-existent hosts or (invalidly) to IP addresses

dig unifrax.cn yields:
;; ANSWER SECTION:
unifrax.cn.             162     IN      MX      5 222.66.19.170.

Apparently, they refuse to fix their DNS entries. There is a mail server
at 222.66.19.170.

I haven't tried ipliteral. Would that work?

Thanks in advance.
David

David Daniels