Block specific files .doc - Aplication and Device Control of SEP 12.1.5

I need to block specific files (.doc), using its md5 hash with Aplication and Device Control  of SEP 12.1.5 (Symantec). This files have a malicious code(SPAMs), that SEP definitions don't recognize (zero day attacks).

I found a lot information about how to block an files .exe, however this information don't is usable, because the spams  come in files with .doc extentions and I need block this specific files and not the extention.

Can you give me some ideas about this?

Thanks you for your help.

Regards
alerpadi