I had a look at RFCs 3501 and 4422 now, and as far as I can see those quote
characters sent by mailkit are unambiguously illegal in IMAP and SASL.
They are, however, almost legal in base64. The base64 spec says that
decoders should/may discard any characters outside the defined set. AAAA
encodes three null bytes. If a decoder skips unknown input, then three null
bytes can also be encoded as "AAAA" "AA"AA", "AAAA', and even "AAAA½",
because ", ½ and ' are not in the base64 set.
I'll ask the mailkit author why mailkit sends quotes.
Arnt
