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7.1 Limitations and omissions
•
Plain text messages: Since IMAP4 is intimately related to the MIME standards, emails sent to
an IMAP4 server which are not in MIME format will not be recognised nor decoded correctly
by the IMAP4 server, nor by the IMAP4 MTM, resulting in the contents of some plain text
emails being formatted incorrectly. This is a limitation of the IMAP4 protocol.
•
Email priorities. IMAP4 does not easily allow the mail client to determine the “priority” (e.g.
high, normal, low) of an email stored on the mail server. The IMAP4 MTM therefore cannot
display the priority of emails on the remote mail server, or in emails that are downloaded from
the remote mail server onto the EPOC device.
•
Uploading emails: The IMAP4 MTM does not support copying or moving email messages
from the EPOC device up onto the remote server (i.e. the IMAP4 “APPEND” command).
Email messages may be sent to the remote mail server from the EPOC device via the usual
route of an SMTP gateway.
•
The IMAP4 MTM does not support “remote folder subscription” - it will ignore the
subscription information retained on the remote mail server.
•
Server defects: Since IMAP4 is a complicated transport protocol, many implementations of
IMAP4 servers do not conform precisely to the IMAP4 rev1 standard. Errors may therefore
occur whilst communicating with an IMAP4 mail server which are due to defects in the server
software, as opposed to being due to defects in the IMAP4 MTM.
•
Modified UTF-7: The IMAP4 does not at present support the modified UTF-7 text encoding
scheme that is defined in the IMAP4 specification.
•
V2.00 of the Messaging Application, and hence the IMAP4 MTM does not support MHTML
Email; body text received in HTML format within an email message will be placed in an
attachment file called “attachment” by the IMAP4 MTM.
7.2 Glossary
The following technical terms and abbreviations are used within this document.
IMAP4 rev1
“Internet Message Access Protocol, Version 4rev1”
an electronic mail transport protocol which allows sophisticated mail operations to be
carried out on a remote mail server by a client.
MTM
“Message Transport Module”
a software “plug-in” which may be installed onto an EPOC device to add dynamically
a new transport protocol service and new functionality to the EPOC Message
Application V2.00
Remote server
The IMAP4 mail server
RFC
“Request For Comments”
an Internet document which defines an Internet standard
