Specifications

IETF groups:

IMAP extensions and server support:

RFC

Name

Capability name

Courier

Cyrus

DBMail

Dovecot

UW-IMAP

IceWarp

lavabit.com

GMail

Isode

2087

IMAP4 QUOTA extension

QUOTA

yes

yes

yes

v1.0

no

yes

no

yes

yes

2088

IMAP4 non-synchronizing literals

LITERAL+

no

v1.5

no

v1.0

yes

no

yes

yes

yes

2177

IMAP4 IDLE command

IDLE

yes

v2.0

yes

v1.0

yes

yes

no

yes

yes

2193

IMAP4 Mailbox Referrals

MAILBOX-REFERRALS

no

v2.1

no

no

yes

no

no

no

no

2221

IMAP4 Login Referrals

LOGIN-REFERRALS

no

no

no

v1.0

yes

no

no

no

no

2342

IMAP4 Namespace

NAMESPACE

yes

v1.6

yes

v1.0

yes

yes

no

yes

yes

2971

IMAP4 ID extension

ID

no

v1.6

no

v1.2

no

yes

no

yes

no

3348

IMAP4 Child Mailbox Extension

CHILDREN

yes

v2.1

yes

v1.0

yes

yes

no

yes

no

3502

IMAP4 MULTIAPPEND Extension

MULTIAPPEND

no

v2.0

no

v1.0

yes

no

no

no

yes

3516

IMAP4 Binary Content Extension

BINARY

no

v2.2

no

v2.2

yes

no

no

no

yes

3691

IMAP4 UNSELECT command

UNSELECT

no

v1.6

yes

v1.0

yes

yes

no

yes

yes

4314

IMAP4 Access Control List (ACL) Extension

ACL

yes

yes

yes

v1.2

no

v10.0

no

no

yes

4314

IMAP4 Access Control List (ACL) Extension

RIGHTS=*

no

v2.3

no

v1.2

no

no

no

no

yes

4315

IMAP UIDPLUS extension

UIDPLUS

yes

v1.6

no

v1.1

yes

yes

no

yes

yes

4467

IMAP - URLAUTH Extension

URLAUTH

no

v2.4

no

v2.2

no

no

no

no

yes

4469

IMAP CATENATE Extension

CATENATE

no

v2.3

no

v2.2

no

no

no

no

yes

4551

IMAP Extension for Conditional STORE Operation or Quick Flag Changes Resynchronization

CONDSTORE

no

v2.3

no

v1.2

no

no

no

no

yes

4731

IMAP4 Extension to SEARCH Command for Controlling What Kind of Information Is Returned

ESEARCH

no

v2.4

no

v1.2

yes

no

no

no

yes

4959

IMAP Extension for Simple Authentication and Security Layer (SASL) Initial Client Response

SASL-IR

no

v2.2

no

v1.1

yes

no

no

no

yes

4978

The IMAP COMPRESS Extension

COMPRESS=DEFLATE

no

v2.4

no

v2.0

no

no

no

yes

no

5032

WITHIN Search Extension to the IMAP Protocol

WITHIN

no

v2.4

no

v1.2

yes

no

no

no

yes

5161

The IMAP ENABLE Extension

ENABLE

no

yes

no

v1.2

no

no

no

no

yes

5162

IMAP4 Extensions for Quick Mailbox Resynchronization

QRESYNC

no

v2.4

no

v1.2

no

no

no

no

yes

5182

IMAP Extension for Referencing the Last SEARCH Result

SEARCHRES

no

no

no

v1.2

no

no

no

no

yes

5255

IMAP Internationalization

I18NLEVEL=1

no

no

no

v1.1

yes

no

no

no

no

5255

IMAP Internationalization

I18NLEVEL=2

no

no

no

no

no

no

no

no

no

5255

IMAP Internationalization

LANGUAGE

no

no

no

no

no

no

no

no

no

5256

IMAP SORT and THREAD Extensions

SORT

yes

v2.0

yes

v1.0

yes

yes

no

no

yes

5256

IMAP SORT and THREAD Extensions

THREAD=ORDEREDSUBJECT

yes

v2.0

yes

v2.1.10

yes

yes

no

no

yes

5256

IMAP SORT and THREAD Extensions

THREAD=REFERENCES

yes

v2.0

no

v1.0

yes

no

no

no

yes

5257

IMAP - ANNOTATE Extension

ANNOTATE-EXPERIMENT-1

no

no

no

no

no

no

no

no

no

5258

IMAP4 - LIST Command Extensions

LIST-EXTENDED

no

v2.4

no

v1.1

no

no

no

no

yes

5259

IMAP - CONVERT Extension

CONVERT

no

no

no

no

no

no

no

no

no

5267

Contexts for IMAP4

ESORT

no

no

no

v1.2

no

no

no

no

no

5267

Contexts for IMAP4

CONTEXT=SEARCH

no

no

no

v1.2

no

no

no

no

yes

5267

Contexts for IMAP4

CONTEXT=SORT

no

no

no

no

no

no

no

no

no

5464

The IMAP METADATA Extension

METADATA

no

no

no

no

no

yes

no

no

no

5465

The IMAP NOTIFY Extension

NOTIFY

no

no

no

v2.2

no

no

no

no

no

5466

IMAP4 Extension for Named Searches (Filters)

FILTERS

no

no

no

no

no

no

no

no

no

5550

The Internet Email to Support Diverse Service Environments (Lemonade) Profile

URL-PARTIAL

no

no

no

v2.2

no

no

no

no

no

5524

Extended URLFETCH for Binary and Converted Parts

URLAUTH=BINARY

no

v2.4

no

v2.2

no

no

no

no

no

5530

IMAP Response Codes

-

no

no

no

v1.2

no

no

no

FIXME

FIXME

5738

IMAP Support for UTF-8

UTF8=*

no

no

no

no

no

no

no

no

no

5819

IMAP4 Extension for Returning STATUS Information in Extended LIST

LIST-STATUS

no

no

no

v1.2

no

no

no

no

no

5957

Display-Based Address Sorting for the IMAP4 SORT Extension

SORT=DISPLAY

no

yes

no

v1.2

no

no

no

no

no

6154

IMAP LIST Extension for Special-Use Mailboxes

SPECIAL-USE

no

no

no

v2.1

no

no

no

no

no

6154

IMAP LIST Extension for Special-Use Mailboxes

CREATE-SPECIAL-USE

no

no

no

no

no

v10.0?

no

no

no

6203

IMAP4 Extension for Fuzzy Search

SEARCH=FUZZY

no

no

no

v2.1

no

no

no

no

no

6237

IMAP4 Multimailbox SEARCH Extension

MULTISEARCH

no

no

no

no

no

no

no

no

no

See also servers' compliancy status.