i found that, for me, checking for a particular charset in header is
not reliable enough. yes, that did some cases, but the majority of
the message bodies were in english, sent by "good people" to various
freebsd mailing lists.
Look for 'asian' in:
If an email has an html-attachment, you might also want
to check the body for charset=$ASIAN.
I block messages firstly on IP-nrs in the IP-chain
(from the Received-headers).
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