Index: horde-webmailer/debian/horde-webmailer/usr/share/horde3/lib/SyncML/Backend/Horde.php
===================================================================
--- horde-webmailer.orig/debian/horde-webmailer/usr/share/horde3/lib/SyncML/Backend/Horde.php	2008-10-20 16:28:27.000000000 +0200
+++ horde-webmailer/debian/horde-webmailer/usr/share/horde3/lib/SyncML/Backend/Horde.php	2008-10-20 16:32:09.000000000 +0200
@@ -178,7 +178,12 @@
         foreach ($data as $suid) {
             // Only server needs to check for client sent entries:
             if ($this->_backendMode == SYNCML_BACKENDMODE_SERVER) {
-                if ($slowsync) {
+                // Add should only be done once on an existing entry -
+                // if it's performed a second time it's very likely that
+                // there is something wrong. Therefore all adds are
+                // filtered that already have a corresponding mapping in
+                // the database
+                //if ($slowsync) {
                     // SlowSync: Ignore all entries where there already in a
                     // map entry.
                     $cuid = $this->_getCuid($database, $suid);
@@ -188,7 +193,7 @@
                             __FILE__, __LINE__, PEAR_LOG_DEBUG);
                         continue;
                     }
-                }
+                //}
                 $suid_ts = $registry->call(
                     $database . '/getActionTimestamp',
                     array($suid,
Index: horde-webmailer/debian/horde-webmailer/usr/share/horde3/lib/Horde/Kolab/IMAP.php
===================================================================
--- horde-webmailer.orig/debian/horde-webmailer/usr/share/horde3/lib/Horde/Kolab/IMAP.php	2008-10-20 16:27:27.000000000 +0200
+++ horde-webmailer/debian/horde-webmailer/usr/share/horde3/lib/Horde/Kolab/IMAP.php	2008-10-20 16:38:34.000000000 +0200
@@ -820,7 +820,17 @@
                         $this->updateHistory($object['uid'], $mod_ts, 'modify');
                         $modified[] = $object['uid'];
                     } else {
-                        $this->updateHistory($object['uid'], $mod_ts, 'add');
+                        // entries that should be added to the history MUST not
+                        // have an existing entry in the history!! otherwise
+                        // they are just marked as "modified"
+                        $history = &Horde_History::singleton();
+                        $history_id = $this->_app_consts['application'] . ':'
+                            . $this->_share_uid . ':' . $object_uid;
+                        if ($history->getActionTimestamp ($history_id, 'add') != 0) {
+                            $this->updateHistory($object['uid'], $mod_ts, 'add');
+                        } else {
+                            $this->updateHistory($object['uid'], $mod_ts, 'modify');
+                        }
                     }
                 } else {
                     $this->_ignoreUid($imap_uid);