2.2.2 IMAP4 Delegate Access Extension Messages
The IMAP4 delegate access extension extends the LOGIN command, as specified in [RFC3501] section 6.2.3. Specifically, it extends the user name argument of the LOGIN command so that a delegate and a delegator can be specified in the login string. This extension only affects the arguments of the LOGIN command and does not change the specification of the LOGIN command in [RFC3501].
There are four formats for the user name argument when using delegate access with IMAP4. The message syntax for the four formats is shown in ABNF.
domain = 1*VCHAR ; The name of the user's domain delegateuseralias = 1*VCHAR ; The delegate's e-mail alias delegateuserupn = 1*VCHAR ; The delegate's UPN principaluseralias = 1*VCHAR ; The principal's e-mail alias principaluserupn = 1*VCHAR ; The principal's UPN password = 1*VCHAR ; The delegate's password delegate_spec = (domain "/" delegateuseralias) / delegateuserupn principal_spec = principaluseralias / principaluserupn IMAP4_DELEGATE_LOGIN_Command = "LOGIN" SP delegate_spec "/" principal_spec SP password
The "domain" part of the login string represents the delegate's domain.
The "delegateuseralias" part of the login string represents the e-mail alias of the delegate.
The "principaluserupn" part of the login string represents the UPN of the primary account, which is composed of the primary account's identifier and domain, as specified in [RFC822] section 6.1.
The "principaluseralias" part of the login string represents the e-mail alias of the primary account.