diff --git a/lib/db/upgrade.php b/lib/db/upgrade.php
index e4a2b0db4e5..5a5b6649d48 100644
--- a/lib/db/upgrade.php
+++ b/lib/db/upgrade.php
@@ -3131,6 +3131,22 @@ function xmldb_main_upgrade($oldversion=0) {
         upgrade_main_savepoint($result, 2007101546.02);
     }
 
+    if ($result && $oldversion < 2007101546.03) {
+    /// Deleting orphaned messages from deleted users.
+        require_once($CFG->dirroot.'/message/lib.php');
+    /// Detect deleted users with messages sent(useridfrom) and not read
+        if ($deletedusers = get_records_sql("SELECT DISTINCT u.id
+                                           FROM {$CFG->prefix}user u
+                                           JOIN {$CFG->prefix}message m ON m.useridfrom = u.id
+                                          WHERE u.deleted = 1")) {
+            foreach ($deletedusers as $deleteduser) {
+                message_move_userfrom_unread2read($deleteduser->id); // move messages
+            }
+        }
+    /// Main savepoint reached
+        upgrade_main_savepoint($result, 2007101546.03);
+    }
+
     return $result;
 }
 
diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index 869ac0c82f2..31da3aa80af 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -3019,6 +3019,7 @@ function delete_user($user) {
     global $CFG;
     require_once($CFG->libdir.'/grouplib.php');
     require_once($CFG->libdir.'/gradelib.php');
+    require_once($CFG->dirroot.'/message/lib.php');
 
     begin_sql();
 
@@ -3029,6 +3030,9 @@ function delete_user($user) {
         }
     }
 
+    //move unread messages from this user to read
+    message_move_userfrom_unread2read($user->id);
+
     // remove from all groups
     delete_records('groups_members', 'userid', $user->id);
 
diff --git a/message/history.php b/message/history.php
index b97ec012d4a..42b3cc55bf5 100644
--- a/message/history.php
+++ b/message/history.php
@@ -20,11 +20,24 @@
         error("User ID 1 was incorrect");
     }
 
+    if ($user1->deleted) {
+        print_header();
+        print_heading(get_string('userdeleted').': '.$userid1);
+        print_footer();
+        die;
+    }
+
     if (has_capability('moodle/site:readallmessages', get_context_instance(CONTEXT_SYSTEM))) {             // Able to see any discussion
         $userid2 = optional_param('user2', $USER->id, PARAM_INT);
         if (! $user2 = get_record("user", "id", $userid2)) {  // Check
             error("User ID 2 was incorrect");
         }
+        if ($user2->deleted) {
+            print_header();
+            print_heading(get_string('userdeleted').': '.$userid2);
+            print_footer();
+            die;
+        }
     } else {
         $userid2 = $USER->id;    // Can only see messages involving yourself
         $user2 = $USER; 
diff --git a/message/lib.php b/message/lib.php
index 3963b896ef3..5a1a3378544 100644
--- a/message/lib.php
+++ b/message/lib.php
@@ -1064,4 +1064,28 @@ function message_print_contactlist_user($contact, $incontactlist = true){
     echo '</tr>';
 }
 
+ /**
+  * Moves unread messages from message table to message_read for a given from user
+  * @param object $userid       User id
+  * @return boolean success
+  */
+function message_move_userfrom_unread2read($userid) {
+
+    // move all unread messages from message table to messasge_read
+    if ($messages = get_records_select('message', "useridfrom = $userid", 'timecreated')) {
+        foreach ($messages as $message) {
+            $message->timeread = 0; //the message was never read
+            $message = addslashes_object($message);
+            $messageid = $message->id;
+            unset($message->id);
+            if (insert_record('message_read', $message)) {
+                delete_records('message', 'id', $messageid);
+            } else {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
 ?>
diff --git a/version.php b/version.php
index 84af4c0fde4..1afd1c47711 100644
--- a/version.php
+++ b/version.php
@@ -6,7 +6,7 @@
 // This is compared against the values stored in the database to determine
 // whether upgrades should be performed (see lib/db/*.php)
 
-    $version = 2007101546.02;  // YYYYMMDD      = date of the 1.9 branch (don't change)
+    $version = 2007101546.03;  // YYYYMMDD      = date of the 1.9 branch (don't change)
                             //         X     = release number 1.9.[0,1,2,3,4,5...]
                             //          Y.YY = micro-increments between releases