diff --git a/admin/user.php b/admin/user.php
index 9ae92ee..dbceb02 100644
--- a/admin/user.php
+++ b/admin/user.php
@@ -27,7 +27,10 @@
 
     $stredit   = get_string('edit');
     $strdelete = get_string('delete');
+    $strundelete = get_string('undelete');
+    $strdeleted = get_string('deleted');
     $strdeletecheck = get_string('deletecheck');
+    $strsearch = get_string('search');
     $strshowallusers = get_string('showallusers');
 
     if (empty($CFG->loginhttps)) {
@@ -67,18 +70,23 @@
             error("You are not allowed to delete the primary admin user!", '', true);
         }
 
-        if ($confirm != md5($delete)) {
-            $fullname = fullname($user, true);
-            print_heading(get_string('deleteuser', 'admin'));
-            $optionsyes = array('delete'=>$delete, 'confirm'=>md5($delete), 'sesskey'=>sesskey());
-            notice_yesno(get_string('deletecheckfull', '', "'$fullname'"), 'user.php', 'user.php', $optionsyes, NULL, 'post', 'get');
-            admin_externalpage_print_footer();
-            die;
-        } else if (data_submitted() and !$user->deleted) {
-            if (delete_user($user)) {
-                notify(get_string('deletedactivity', '', fullname($user, true)) );
-            } else {
-                notify(get_string('deletednot', '', fullname($user, true)));
+        if ($user->deleted) {
+            undelete_user($user);
+            notify(get_string('undeleteduser', 'admin', $user));
+        } else {
+            if ($confirm != md5($delete)) {
+                $fullname = fullname($user, true);
+                print_heading(get_string('deleteuser', 'admin'));
+                $optionsyes = array('delete'=>$delete, 'confirm'=>md5($delete), 'sesskey'=>sesskey());
+                notice_yesno(get_string('deletecheckfull', '', "'$fullname'"), 'user.php', 'user.php', $optionsyes, NULL, 'post', 'get');
+                admin_externalpage_print_footer();
+                die;
+            } else if (data_submitted() and !$user->deleted) {
+                if (delete_user($user)) {
+                    notify(get_string('deletedactivity', '', fullname($user, true)) );
+                } else {
+                    notify(get_string('deletednot', '', fullname($user, true)));
+                }
             }
         }
     } else if ($acl and confirm_sesskey()) {
@@ -213,10 +221,13 @@
             if ($user->id == $USER->id) {
                 $deletebutton = "";
             } else {
+                $deletebutton = "";
                 if (has_capability('moodle/user:delete', $sitecontext)) {
-                    $deletebutton = "<a href=\"user.php?delete=$user->id&amp;sesskey=$USER->sesskey\">$strdelete</a>";
-                } else {
-                    $deletebutton ="";
+                    if ($user->deleted) {
+                        $deletebutton = "<a href=\"user.php?delete=$user->id&amp;sesskey=$USER->sesskey\">$strundelete</a>";
+                    } else {
+                        $deletebutton = "<a href=\"user.php?delete=$user->id&amp;sesskey=$USER->sesskey\">$strdelete</a>";
+                    }
                 }
             }
 
@@ -266,7 +277,13 @@
             }
             $fullname = fullname($user, true);
 
-            $table->data[] = array ("<a href=\"../user/view.php?id=$user->id&amp;course=$site->id\">$fullname</a>",
+            $deletedmark = '';
+            if ($user->deleted) {
+                $deletedmark = '<abbr title="' . get_string('userdeleted','admin') . '">' . get_string('deletedmark', 'admin') . '</abbr>';
+                $editbutton = '';
+            }
+
+            $table->data[] = array ("$deletedmark<a href=\"../user/view.php?id=$user->id&amp;course=$site->id\">$fullname</a>",
                                 "$user->email",
                                 "$user->city",
                                 "$user->country",
diff --git a/lang/en_utf8/admin.php b/lang/en_utf8/admin.php
index 28450b7..7b13b54 100644
--- a/lang/en_utf8/admin.php
+++ b/lang/en_utf8/admin.php
@@ -276,6 +276,7 @@ $string['defaultrequestcategory'] = 'Default category for course requests';
 $string['defaultsettinginfo'] = 'Default: $a';
 $string['defaultuserroleid'] = 'Default role for all users';
 $string['defaultvalues'] = 'Default values';
+$string['deletedmark'] = '[x]';
 $string['deleteerrors'] = 'Delete errors';
 $string['deleteunconfirmed'] = 'Delete unconfirmed users after';
 $string['deleteuser'] = 'Delete user';
@@ -656,6 +657,7 @@ $string['timezonenotforced'] = 'Users can choose their own timezone';
 $string['tokenizerrecommended'] = 'Installing the optional PHP Tokenizer extension is recommended -- it improves Moodle Networking functionality.';
 $string['unattendedoperation'] = 'Unattended operation';
 $string['unbookmarkthispage'] = 'unbookmark this page';
+$string['undeleteduser'] = 'The user has been undeleted. However, please note that course enrolments and group membership cannot be restored automatically.';
 $string['unicodeupgradenotice'] = 'In Moodle 1.6 we have migrated all languages to Unicode.  To complete the upgrade for this site, you need to convert all the data in your database to Unicode (UTF-8) using our migration script.  <a href=\"utfdbmigrate.php\">Click here to run the migration script now</a>!';
 $string['unicoderecommended'] = 'Storing all your data in Unicode (UTF-8) is recommended. New installations should be performed into databases that have their default character set as Unicode.  If you are upgrading, you should perform the UTF-8 migration process (see the Admin page).';
 $string['unicoderequired'] = 'It is required that you store all your data in Unicode format (UTF-8). New installations must be performed into databases that have their default character set as Unicode.  If you are upgrading, you should perform the UTF-8 migration process (see the Admin page).';
diff --git a/lang/en_utf8/moodle.php b/lang/en_utf8/moodle.php
index df3373e..223e367 100644
--- a/lang/en_utf8/moodle.php
+++ b/lang/en_utf8/moodle.php
@@ -1486,6 +1486,7 @@ $string['trysearching'] = 'Try searching instead.';
 $string['turneditingoff'] = 'Turn editing off';
 $string['turneditingon'] = 'Turn editing on';
 $string['undecided'] = 'Undecided';
+$string['undelete'] = 'Undelete';
 $string['unenrol'] = 'Unenrol';
 $string['unenrolroleusers'] = 'Unenrol users';
 $string['unenrolallstudents'] = 'Unenrol all students';
diff --git a/lib/datalib.php b/lib/datalib.php
index db589a4..0559421 100644
--- a/lib/datalib.php
+++ b/lib/datalib.php
@@ -305,7 +305,7 @@ function get_users_listing($sort='lastaccess', $dir='ASC', $page=0, $recordsperp
     $LIKE      = sql_ilike();
     $fullname  = sql_fullname();
 
-    $select = "deleted <> '1'";
+    $select = "id > 0";
 
     if (!empty($search)) {
         $search = trim($search);
@@ -329,7 +329,7 @@ function get_users_listing($sort='lastaccess', $dir='ASC', $page=0, $recordsperp
     }
 
 /// warning: will return UNCONFIRMED USERS
-    return get_records_sql("SELECT id, username, email, firstname, lastname, city, country, lastaccess, confirmed, mnethostid
+    return get_records_sql("SELECT id, username, email, firstname, lastname, city, country, lastaccess, confirmed, mnethostid, deleted
                               FROM {$CFG->prefix}user
                              WHERE $select $sort", $page, $recordsperpage);
 
diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index 6415a36..0384d73 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -2860,6 +2860,25 @@ function truncate_userinfo($info) {
 }
 
 /**
+ * Unmarks user as deleted, and tries to restore the username, idnumber and email address
+ */
+function undelete_user($user) {
+    global $CFG;
+
+    $updateuser = new stdclass;
+    $updateuser->id = $user->id;
+    $updateuser->deleted = 0;
+    $updateuser->username = get_user_preferences('old_username');
+    $updateuser->idnumber = get_user_preferences('old_idnumber');
+    $updateuser->email    = get_user_preferences('old_email');
+    $updateuser->timemodified = time();
+    // Don't undelete them if we coudln't find a username and email, at least.
+    if (!empty($updateuser->username) && !empty($updateuser->email)) {
+        update_record('user', $updateuser);
+    }
+}
+
+/**
  * Marks user deleted in internal user database and notifies the auth plugin.
  * Also unenrols user from all roles and does other cleanup.
  * @param object $user       Userobject before delete    (without system magic quotes)
@@ -2894,6 +2913,10 @@ function delete_user($user) {
         $delname++;
     }
 
+    set_user_preference('old_username', $user->username);
+    set_user_preference('old_idnumber', $user->idnumber);
+    set_user_preference('old_email', $user->email);
+
     // mark internal user record as "deleted"
     $updateuser = new object();
     $updateuser->id           = $user->id;