diff --git a/mail.php b/mail.php
index 19115a8..06ed9a9 100644
--- a/mail.php
+++ b/mail.php
@@ -1049,10 +1049,10 @@ class mail
     $date = rtrim ($this->getDate ());
     if ($date !== false)
     {
-      $dateTimestamp = DateTime::createFromFormat (DateTime::RFC2822,
+      $dateTimestamp = \DateTime::createFromFormat (\DateTime::RFC2822,
                                                    $date);
       if ($dateTimestamp === false)
-        $dateTimestamp = DateTime::createFromFormat (DateTime::RFC822,
+        $dateTimestamp = \DateTime::createFromFormat (\DateTime::RFC822,
                                                      $date);
       if ($dateTimestamp !== false)
         $dateTimestamp  = $dateTimestamp->getTimestamp();