diff --git a/rest.php b/rest.php
index ddd884fcd..107801829 100644
--- a/rest.php
+++ b/rest.php
@@ -44,7 +44,7 @@
         $vocab = $parts[1];
         try {
             $request->setVocab($parts[1]);
-        } catch (Exception $e) {
+        } catch (Exception | ValueError $e) {
             header("HTTP/1.0 404 Not Found");
             header("Content-type: text/plain; charset=utf-8");
             echo ("404 Not Found : Vocabulary id '$parts[1]' not found.");