diff --git a/lib/messagelistitem.php b/lib/messagelistitem.php
index 2590d7df63..cb9e546f0b 100644
--- a/lib/messagelistitem.php
+++ b/lib/messagelistitem.php
@@ -109,8 +109,10 @@ abstract class MessageListItem extends Widget
                                             'class' => 'timestamp',
                                             'href' => $messageurl));
         $dt = common_date_iso8601($this->message->created);
-        $this->out->element('abbr', array('class' => 'published',
-                                          'title' => $dt),
+        $this->out->element('time', array('class' => 'dt-published',
+                                          'datetime' => common_date_iso8601($this->message->created),
+                                          // TRANS: Timestamp title (tooltip text) for NoticeListItem
+                                          'title' => common_exact_date($this->message->created)),
                             common_date_string($this->message->created));
         $this->out->elementEnd('a');
 
diff --git a/lib/noticelistitem.php b/lib/noticelistitem.php
index 6aef97a1a4..e82331afed 100644
--- a/lib/noticelistitem.php
+++ b/lib/noticelistitem.php
@@ -370,9 +370,10 @@ class NoticeListItem extends Widget
         $this->out->elementStart('a', array('rel' => 'bookmark',
                                             'class' => 'timestamp',
                                             'href' => $noticeurl));
-        $dt = common_date_iso8601($this->notice->created);
-        $this->out->element('abbr', array('class' => 'published',
-                                          'title' => $dt),
+        $this->out->element('time', array('class' => 'dt-published',
+                                          'datetime' => common_date_iso8601($this->notice->created),
+                                          // TRANS: Timestamp title (tooltip text) for NoticeListItem
+                                          'title' => common_exact_date($this->notice->created)),
                             common_date_string($this->notice->created));
         $this->out->elementEnd('a');
     }
diff --git a/lib/util.php b/lib/util.php
index aa6a59c9aa..8a259df7c1 100644
--- a/lib/util.php
+++ b/lib/util.php
@@ -1393,7 +1393,8 @@ function common_exact_date($dt)
     $dateStr = date('d F Y H:i:s', strtotime($dt));
     $d = new DateTime($dateStr, $_utc);
     $d->setTimezone($_siteTz);
-    return $d->format(DATE_RFC850);
+    // TRANS: Human-readable full date-time specification (formatting on http://php.net/date)
+    return $d->format(_('l, d-M-Y H:i:s T'));
 }
 
 function common_date_w3dtf($dt)
diff --git a/plugins/GroupPrivateMessage/lib/groupmessagelistitem.php b/plugins/GroupPrivateMessage/lib/groupmessagelistitem.php
index 741d621c32..ee0f147305 100644
--- a/plugins/GroupPrivateMessage/lib/groupmessagelistitem.php
+++ b/plugins/GroupPrivateMessage/lib/groupmessagelistitem.php
@@ -99,9 +99,10 @@ class GroupMessageListItem extends Widget
         $this->out->elementStart('a', array('rel' => 'bookmark',
                                             'class' => 'timestamp',
                                             'href' => $this->gm->url));
-        $dt = common_date_iso8601($this->gm->created);
-        $this->out->element('abbr', array('class' => 'published',
-                                          'title' => $dt),
+        $this->out->element('time', array('class' => 'dt-published',
+                                          'datetime' => common_date_iso8601($this->gm->created),
+                                          // TRANS: Timestamp title (tooltip text) for NoticeListItem
+                                          'title' => common_exact_date($this->gm->created)),
                             common_date_string($this->gm->created));
         $this->out->elementEnd('a');
         $this->out->elementEnd('div');