Fixed warnings. (time for reviewing my php.ini and find out why those

warnings were not displayed on my screen)

functions/mailbox_display.php

@@ -1138,7 +1138,7 @@ function mail_message_listing_beginning ($imapConnection,
                                          $paginator = ' '
                                         ) {
     global $color, $show_flag_buttons, $PHP_SELF;
-    global $lastTargetMailbox;
+    global $lastTargetMailbox, $boxes;
 
     $php_self = $PHP_SELF;
 

src/read_body.php

@@ -858,7 +858,7 @@ if (isset($sendreceipt)) {
       if ( SendMDN( $mailbox, $passed_id, $final_recipient, $message, $imapConnection ) > 0 && $supportMDN ) {
          ToggleMDNflag( true, $imapConnection, $mailbox, $passed_id);
          $message->is_mdnsent = true;
-         $messages[$uidvalidity][$passed_id]=$message;
+         $aMailbox['MSG_HEADERS'][$passed_id]['MESSAGE_OBJECT'] = $message;
       }
       ClearAttachments();
    }