Hi Richard,
You could try setup a content filter in SM. Looking either in the header or the body for the following character sets:
Chinese Simplified (GB18030) GB18030
Chinese Simplified (GB2312) GB2312
Chinese Simplified (HZ) HZ
Chinese Traditional (Big5) Big5
You would look for a string like charset=Big5
The other option is to use a 3rd party product like
Declude which is free. It has the built in ability to block Character sets.
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