IMAP Server Compliancy Status

Fully compliant servers:

Server

Checkpoint

\Recent

Atomic flags

Expunge fetch

Expunge store

Failure groups

Base fails

Ext fails

Dovecot 1.1.5+

Yes

Yes

Yes

Yes / Cached (depends on storage)

Yes

0/40

0/403

0/100

Panda IMAP 2008, mix format

Yes

Yes

Yes

Yes

Session

0/34

0/328

0/97

Non-compliant servers:

Server

Checkpoint

\Recent

Atomic flags

Expunge fetch

Expunge store

Failure groups

Base fails

Ext fails

UW-IMAP 2007b, mix format

Yes

Yes

Yes

Yes

Session

2/34

0/328

6/53

Isode M-Box 14.3a0

No

Unreliable

Yes

Cached

Ignored

4/40

1/408

8/112

Dovecot 1.0.15

Yes

Unreliable

Bugs

Cached

Yes

2/34

4/328

2/53

CommuniGate Pro 5.2.1

Yes

Yes

Yes

Cached (some)

No

8/34

8/328

0/0

Cyrus 2.3.12p2

No

Unreliable

Bugs

Cached

Delayed

9/34

11/328

6/53

Sun Java Messenging Server 6.3-0.15

No

Unreliable

Bugs

Yes

Delayed

9/34

17/328

9/21

Archiveopteryx 3.0.3

No

Unreliable

No

No

No

13/38

25/346

6/26

Courier 4.3.1

Yes

Unreliable

Yes

No

No

18/34

33/328

20/53

GMail 2008-09-20

No

Not implemented

Bugs

Yes (but FETCH FLAGS dies)

No

15/34

36/328

0/0

Zarafa 6.20

No

Unreliable

Yes

No

No

15/40

41/403

0/0

Zimbra 5.0.5

Yes

Yes

Yes

Cached

No

8/34

50/328

2/33

MS Exchange

No

Unreliable

?

No

No

16/40

52/287

0/0

Citadel 7.36

No

Unreliable

Yes

Yes

Session (flag changes are never seen by other sessions)

19/34

98/328

0/0

dbmail 2.3.4 (2.3.x = unstable/dev version - 2.2.x is even worse though)

No

Unreliable

No

Yes

Delayed (always)

Crashes in the middle.

Major problems with multiple connections (makes further testing difficult and MAY CAUSE ACCIDENTAL MAIL LOSS!):

Server

Checkpoint

\Recent

Atomic flags

Expunge fetch

Expunge store

Failures

IBM Domino 8.0

No

Unreliable

?

?

No

16/34 - Too many EXPUNGEs are sent, EXISTS is dropped before sending EXPUNGEs, FETCHing with valid messagesets produce errors

Kerio Mail Server 6.5.1

?

?

?

?

?

18/34 - EXPUNGEs are sent wrong

Axigen 7.1.2

?

Unreliable

Yes

Broken

Broken

19/312 - FETCH/STORE sends EXPUNGEs immediately