[kde-linux] kmail and base64 encoded jpg files

[Pollywog]

Every once in a while, someone will send me pictures of their pets in their 
emails and most of the time, I can see the pictures in kmail by 
selecting "view", but sometimes when the sender is a Windows user and not a 
Mac user, kmail does not show the picture.  If I save it, I also cannot see 
it and "file" reports the saved file is empty.  If I use Thunderbird however, 
I can see the picture.  Then if I go back to kmail, I can see the picture.  
The problem pictures are almost always shown as "base64" in kmail.

Is this a bug in kmail?