[X4U] Embedded images in Mail

[lancew]

In the Mail program is the option to "Display images and embedded 
objects in HTML messages" which I have unchecked. This prevents images 
from being shown in about 95% of my emails (they display as little blue 
question marks), but recently I have been getting more and more emails, 
mostly from pill spammers, that are showing images inline. The 
following is the image tag from one of the emails:

(open bracket)
I=MG alt=3D"" hspace=3D0 
src=3D"cid:338614c4d3c0$2180fea0$954aa0c0 at NLCMYDMY" align=3Dbas=eline 
border=3D0
(close bracket)

It looks like they are bypassing everything in Mail by just inserting 
an '=' in the middle of words. What I want to know is how can I prevent 
this from happening at all, and also is this only for embedded images 
or will this trick allow the email to tell Mail to go out to some 
server to grab an image, thereby tracking my email?

This isn't just happening in spam messages either. I received an email 
from a legit company that had attached two pdfs to the end of their 
email. One of them displayed inline and the other was just the normal 
acrobat icon with a link.

Whatever happened to the days of good ol' plain text email?

Thanks,

lance