IMAP support on different mail servers

Question

To interact with several different mail servers via IMAP (using javamail), I found that among them there is other support for IMAP functions. The lack of support for some functions led to an increase in development time, more complex code for working with various support, performance degradation due to the inability to search, etc.

Therefore, I would like to receive information about other servers and the level of support that they provide. So far, I have dealt with Lotus Domino and Novell GroupWise (and to a lesser extent with Exchange 2003 and 2007). I am particularly interested in most used in unix / linux ( Courier, Cyrus, Dovecot, UW IMAP ), as well as Zimbra , but do not hesitate to add friends. Information about online services such as gmail is also welcome .

Opportunities that I consider (comment if you are interested in others, and I will add them.

• Custom flags
• Search for custom flags
• Search for custom headers
• Partial sampling
• Proxy authentication

And what I have found so far (correct if I'm wrong somewhere):

Lotus domino

• Custom flags yes
• ?
• - , , '\ Other Users'

Novell GroupWise

• ?
• - ,

Dovecot

• :
• : yes
• : yes
• :
• -:?

: "FLAGS" SELECT/EXAMINE "PERMANENTFLAGS" SELECT. , . , .

Gmail

• :
• : yes
• : yes
• :
• -: no

! , , ( , )

Answer 1

, . ( Exchange 2003 & 2007 Courier).

Dovecot

• :
• :
• :
• :
• -:?

: "FLAGS" SELECT/EXAMINE "PERMANENTFLAGS" SELECT. , . , .

Gmail

• :
• :
• :
• :
• -:

: , .

Answer 2

Gmail IMAP-, PROXYAUTH:

---
* OK Gimap ready for requests from 1.1.1.1 wi9if8940621pbc.126
A001 LOGIN testuser testpassword
* CAPABILITY IMAP4rev1 UNSELECT IDLE NAMESPACE QUOTA ID XLIST CHILDREN X-GM-EXT-1 UIDPLUS COMPRESS=DEFLATE
A001 OK testuser Test User authenticated (Success)
A001 PROXYAUTH someotheruser
A001 BAD Unknown command: PROXYAUTH