[imp] IMP, PHP, IMAP and remote servers problem

[Diego Rivera]

Hello all..

Granted, I've not read the docs, but I've set up IMP/HORDE/et al
successfully several times, and know my way around it fairly well (I
think).

I'm running into a bit of a problem that really has me stumped - mostly
because I can find no real logical reason for it to occurr.  And thus, I
turn to you guys for assistance.

I have two servers: one is a WEB/IMAP server (Mdk 9.0), and the other is
IMAP-only (RHAS 2.1 - all necessary updates).  This is a
proof-of-concept environment,

The idea is to have horde/imp/etc. running in the web server and use the
'preferred' attribute to select which IMAP server the user connects to.

While the host selection works (i.e. login is attempted to the correct
machine), IMAP only works with LOCAL connections...that is to say:
connecting to the IMAP that runs on the web server works fine, but
connecting to the IMAP that runs on the OTHER server does not.

Checking the logs yields little info, since horde.log just shows "LOGIN
FAILED...etc", and the logs on the other server show a premature
connection death (although the establishment of the tcp connection
proper seems to have succeeded).

The strangest thing of all is: I set up a test account in evolution to
check to see if IMAP itself was broken on the second server, and that
test account works fine!!  I can read, delete, etc.

Even stranger:  Copied IMP/HORDE/etc over to the server, set it up, and
I can log in and work fine...LOCALLY!!  Set up the reverse-case (i.e.
switched server roles), and the problem shows up again (but inverted).

Why would the IMP/PHP/Horde IMAP driver be broken for over-the-network
connections, but not local ones?  I conceive them both to be exactly the
same.

FYI: I do NOT use localhost or 127.0.0.1 as the addresses for any of the
connection strings...

What am I missing?  Maybe some parameter in php.ini that needs to be
set?

A new brain?  A new profession?

Best

-- 
Diego Rivera <lrivera at racsa.co.cr>