[horde] strange problem on login

[Jens-U. Mozdzen]

Hi list,

we just experienced a strange error situation and I felt like asking  
if anyone had seen this already:

I've been successfully using an up-to-date H5 server on client machine  
A (openSUSE 12.2, Firefox 17.0), user 1.

Today I had to use another client machine at a different location  
(similar to client A - openSUSE 12.2, Firefox 17.0, latest patches),  
again as user 1:

- I logged in to H5, got the portal view (dynamic), current emails etc  
were listed
- I clicked to see my inbox, but got a Horde report about a severe  
server error "with details in the log" (the log reported that the  
e-mail server wouldn't support secure connection)

- logout, login -> get portal as above
- click "reload page" button of browser: no emails, no dates, etc. and  
Horde's log fills with "e-mail server doesn't support secure  
connections" messages

My first guess were cookie problems, so I deleted all cookies for that  
server, even those for other applications, and made sure there's no  
exception entry (block all cookies from host) in the browser config.  
Then restarted the browser, but symptoms as above.

Using a test user account (user 2) with the same browser on client B,  
things worked flawlessly. But a third user reported the same symptoms  
as I have, but from a different machine C.

So:
- It's not caused by the account alone (works on client A, fails on client B)
- It's not caused by the client alone (using the same client, user 2  
works but user 1 fails)
- Accessing the IMAP server works at the start of the session, as I  
can see new emails and calendar entries in the portal view, until the  
first reload.

To cut a long story short: After deleting the Horde cache on the  
server and restarting the Apache httpd, everything was fine. No  
problems since then.

So:
- It's not caused by the (Horde, IMAP) server configuration alone  
(cache cleared - now it fully works)

All affected clients were used to access Horde4 on the same server and  
probably had old cookies with a matching path stored in the user  
profile. But we have more than one machine which was used for old  
Horde accounts as well, that didn't exhibit this behavior.

Has anyone seen something similar or maybe even has an explanation? Is  
it the consequence of a wrongly configured Horde server? I'm puzzled,  
and of course am not always in the situation to clear the cache and  
restart the server in production...

With regards,
Jens