How do I check for a jpeg attachment?

[Loren Wilton]

I'm getting a bunch of spams from fake gmail accounts that consist of one 
short line of text and a 2 MB jpg file.
The subject and body text are pretty much random beyond that.
How do I check for the following?

--000000000000e345f305ea2680cd
Content-Type: image/jpeg; name="MMM.jpg"
Content-Disposition: attachment; filename="MMM.jpg"
Content-Transfer-Encoding: base64
Content-ID: <f_l8t6clr50>
X-Attachment-Id: f_l8t6clr50

I want to match on /^Content-Type: image\/jpeg;/ but I can't figure out how 
to do that. rawbody doesn't seem to work.

Thanks