Subject that is encoded with a character set

I want to create a mail flow rule that will bump the SCL of an email with Chinese characters in the subject.  I tried creating a rule whose subject matches the expression '=\?utf-8\?' or '=\?gb18030\?' or '=\?gb2312\?' or '=\?gbk\?' or '(=\?utf-8\?|=\?GB(K|2312|18030)\?)' however, it doesn't work. 

I think what happens is Exchange searches after interpreting the subject's encoding, as opposed to searching the subject header raw. 

Any ideas how I can accomplish my mail flow rule?

thanks!