Comment 20 for bug 1068921

Just waiting for my local checkout to build so that I can do a proper bisect, but these 2 commits might be a clue:

changeset: 10468:5a6bee217340
user: Irving Reid <email address hidden>
date: Tue Jun 19 08:55:19 2012 -0700
summary: Bug 92111 (and bug 390795, and many others) - correctly handle case where we're downloading IMAP body in chunks, and the server lies about RFC822.SIZE,r=bienvenu

changeset: 10469:0401e822b882
user: Irving Reid <email address hidden>
date: Tue Jun 19 09:00:03 2012 -0700
summary: Bug 740453: Investigate download whole message vs. download in chunks,r=bienvenu