9D character used in words to avoid detection.

[Mark London]

I just received a spam email with the 9D character placed inside of 
words, that prevented my custom BODY rules from being hit.  I.e.:

Obvi=9Do=9Dusly yo=9Du=9D ca=9Dn can cha=9Dnge=9D i=9Dt, o=9Dr 
a=9Dlready change=9Dd it.

Is there a way to define BODY rules, so that they will be triggered?   
Thanks.

Mark