Inbound emails have = characters.
I am tracing the inbound email function and I have got all the way back to function getFormattedRawSource in InboundEmail.php.
Interestingly the raw_source field is empty in the table of emails already in the system. This indicates to me a separate function is populating the table record with thie field info as a temporary holding location and then the email is parsed and the field is emptied.
I added a debug line in the function to output $raw to the log and the message body is output as each line being fixed character width terminated by the = sign and a newline character. This is not the actual formatting of the source of the email so now I am trying to find which script and function is breaking the message text source into fixed character width with = on the end?