Index: wp-includes/pomo/mo.php
===================================================================
--- wp-includes/pomo/mo.php	(revision 23307)
+++ wp-includes/pomo/mo.php	(working copy)
@@ -207,7 +207,8 @@
 			$translation = $reader->substr( $strings, $t['pos'], $t['length'] );
 
 			if ('' === $original) {
-				$this->set_headers($this->make_headers($translation));
+				$headers = $this->make_headers($translation);
+				$this->set_headers($headers);
 			} else {
 				$entry = &$this->make_entry($original, $translation);
 				$this->entries[$entry->key()] = &$entry;
Index: wp-includes/pomo/po.php
===================================================================
--- wp-includes/pomo/po.php	(revision 23307)
+++ wp-includes/pomo/po.php	(working copy)
@@ -223,7 +223,8 @@
 			$res = $this->read_entry($f, $lineno);
 			if (!$res) break;
 			if ($res['entry']->singular == '') {
-				$this->set_headers($this->make_headers($res['entry']->translations[0]));
+				$headers = $this->make_headers($res['entry']->translations[0]);
+				$this->set_headers($headers);
 			} else {
 				$this->add_entry($res['entry']);
 			}