[horde] Horde Activesync - Problem loading mail folders from IMAP server: IMP is marked as authenticated, but no credentials can be found in the session."

[django jango]

Dear Team

I have installed Horde 5.1.2 and facing problem  while configuring
ActiveSync on any of iphone, android phone. I am getting following error

"Problem loading mail folders from IMAP server: IMP  is marked as
authenticated, but no credentials can be found in the session."

Wheras IMP is working fine, I am able to login, send and receive email.
I have selected authatication by application and selected application is
IMP from the GUI configuration.

Here are active sync logs

2013-08-06T10:50:26+00:00 INFO: [1766] Replacing SYNC_CACHE entry for user
test at test.com.in and device 094DBA36F0DB11A886509569CD0000BF:
a:11:{s:18:"confirmed_synckeys";a:0:{}s:17:"lasthbsyncstarted";b:0;s:17:"lastsyncendnormal";b:0;s:9:"timestamp";s:10:"1375786226";s:4:"wait";b:0;s:10:"hbinterval";b:0;s:7:"folders";a:0:{}s:9:"hierarchy";s:1:"0";s:11:"collections";a:0:{}s:13:"pingheartbeat";b:0;s:14:"synckeycounter";a:0:{}}
2013-08-06T10:50:26+00:00 DEBUG: [1766] I  </FolderHierarchy:FolderSync>
2013-08-06T10:50:26+00:00 INFO: [1766] Initializing folder diff engine
2013-08-06T10:50:26+00:00 INFO: [1766]
Horde_Core_ActiveSync_Driver::getFolderList()
2013-08-06T10:50:26+00:00 INFO: [1766] Polling
Horde_Core_ActiveSync_Driver::_getMailFolders()
2013-08-06T10:50:26+00:00 ERR: [1766] Problem loading mail folders from
IMAP server: IMP is marked as authenticated, but no credentials can be
found in the session.
2013-08-06T10:50:26+00:00 ERR: IMP is marked as authenticated, but no
credentials can be found in the session.
2013-08-06T10:50:26+00:00 INFO: [1766] No folder changes found.
2013-08-06T10:50:26+00:00 DEBUG: [1766] O  <FolderHierarchy:FolderSync>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O   <FolderHierarchy:Status>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O    1
2013-08-06T10:50:26+00:00 DEBUG: [1766] O   </FolderHierarchy:Status>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O   <FolderHierarchy:SyncKey>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O    0
2013-08-06T10:50:26+00:00 DEBUG: [1766] O   </FolderHierarchy:SyncKey>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O   <FolderHierarchy:Changes>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O    <FolderHierarchy:Count>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O     0
2013-08-06T10:50:26+00:00 DEBUG: [1766] O    </FolderHierarchy:Count>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O   </FolderHierarchy:Changes>
2013-08-06T10:50:26+00:00 DEBUG: [1766] O  </FolderHierarchy:FolderSync>
2013-08-06T10:50:26+00:00 INFO: [1766] Replacing SYNC_CACHE entry for user
test at test.com and device 094DBA36F0DB11A886509569CD0000BF:
a:11:{s:18:"confirmed_synckeys";a:0:{}s:17:"lasthbsyncstarted";b:0;s:17:"lastsyncendnormal";b:0;s:9:"timestamp";s:10:"1375786226";s:4:"wait";b:0;s:10:"hbinterval";b:0;s:7:"folders";a:0:{}s:9:"hierarchy";s:1:"0";s:11:"collections";a:0:{}s:13:"pingheartbeat";b:0;s:14:"synckeycounter";a:0:{}}
2013-08-06T10:50:26+00:00 INFO: [1766] User test at test.com logged off


Here is the configuration details for the Active sync

# vi /var/www/horde/config/conf.php

$conf['activesync']['emailsync'] = true;
$conf['activesync']['version'] = '14.1';
$conf['activesync']['autodiscovery'] = 'full';
$conf['activesync']['outlookdiscovery'] = false;
$conf['activesync']['logging']['path'] = '/tmp';
$conf['activesync']['logging']['type'] = 'custom';
$conf['activesync']['ping']['forcedheartbeat'] = 60;
$conf['activesync']['ping']['deviceping'] = false;
$conf['activesync']['ping']['waitinterval'] = 15;
$conf['activesync']['enabled'] = true;


#vi  /etc/httpd/conf/httpd.conf

Alias /Microsoft-Server-ActiveSync /var/www/xmail142/rpc.php
Alias /autodiscover/autodiscover.xml /var/www/xmail142/rpc.php


Any help is appreciated!
Deepak