[imp] Redirect loop on IMP auth

[Jaz]

Jaz wrote:

>>>IMP, at authentication, is cycling the following into my Apache2 log in
>>>an endless loop. This is after upgrading Apache from 1.3 to 2.0.54 and
>>>PHP from 4.3 to 5.0.4 (and PEAR). I have hordeauth set to true in
>>>imp/servers.php -- set to false the result is a simple IMP login failure.)
>>>   
>>>      
>>>
>>Are you sure the horde password is the same as the IMP password?
>>    
>>
>horde is uses IMP for authentication (in horde's conf.php file:
>$conf['auth']['driver'] = 'imap'; ) and IMP should use the session
>(imp's servers.php file:  'hordeauth' => true, )
>
>Nothing in my horde tree changed when I upgraded to Apache2 & PHP5. So
>I'm guessing it's something to do with tighter session stuff in one or
>both of the newer Apache/PHP(??) I'm thinking the fix is somewhere in
>php.ini or httpd.conf.
>  
>

More...
I saw these in horde.log, which led me to believe that perhaps it's a 
stored certificate  or cookie in my browser:

Jun 30 11:50:03 HORDE [notice] [imp] 172.16.30.101  [on line 31 of 
"D:\HTSERV\HTDOCS\horde\imp\login.php"]
Jun 30 11:50:04 HORDE [info] [imp] Invalid server key "" from client 
[172.16.30.101] [on line 143 of "D:\HTSERV\HTDOCS\horde\imp\redirect.php"]

So I set hordeauth to false to force a separate IMP login:

Jun 30 11:51:18 HORDE [notice] [imp] 172.16.30.101  [on line 31 of 
"D:\HTSERV\HTDOCS\horde\imp\login.php"]
Jun 30 11:51:35 HORDE [error] [imp] FAILED LOGIN 172.16.30.101 to 
127.0.0.1:143[imap/notls] as jaz [on line 247 of 
"D:\HTSERV\HTDOCS\horde\imp\lib\Auth\imp.php"]
Jun 30 11:51:36 HORDE [debug] [] SQL Query by Prefs_sql::retrieve(): 
SELECT pref_scope, pref_name, pref_value FROM horde_prefs WHERE pref_uid 
= 'jaz' AND (pref_scope = 'imp' OR pref_scope = 'horde') ORDER BY 
pref_scope [on line 147 of "D:\HTSERV\HTDOCS\horde\lib\Horde\Prefs\sql.php"]
Jun 30 11:51:36 HORDE [notice] [imp] 172.16.30.101 failed [on line 31 of 
"D:\HTSERV\HTDOCS\horde\imp\login.php"]

I don't see a stored certificate but did remove auth_key and imp_key 
cookies, but no improvement. I can login to horde using IMAP for 
authentication, but can't get into IMP.

Does anyone get anything out of this?
Jaz