Created attachment 1633 [details]
The broken and fixed mail files
I am unable to identify what is special about these messages. All I know is that they are sent by one specific person using Gmail. Other messages coming from Gmail do not seem to have this error.
My workaround has been to create an action that deletes the message. When the message is re-downloaded, it appears correctly.
This is the action, in case someone else has this problem and needs this workaround:
/bin/bash -c "rm %F"
I am attaching an example message -- first the broken version, and then the working version that I get after I run the action.
Note that I have obfuscated the message by changing both sender and receiver to "secret". Otherwise they are exactly as I received them.
The Network Log would be more useful than your examples of mails.
*** This bug has been marked as a duplicate of bug 3278 ***
It seems that you already know about this bug. Do you still want my logs? Do I need to run in --debug mode in order to generate them?