diff --git a/js/jquery-comments.js b/js/jquery-comments.js
index d2f98bf..4ef14c1 100644
--- a/js/jquery-comments.js
+++ b/js/jquery-comments.js
@@ -932,7 +932,7 @@
                 parent: textarea.attr('data-parent') || null,
                 content: this.getTextareaContent(textarea),
                 pings: this.getPings(textarea),
-                modified: new Date().getTime()
+                modified: new Date().toISOString()
             });
 
             // Reverse mapping
@@ -2315,4 +2315,4 @@
             comments.init(options || {}, this);
         });
     };
-}));
\ No newline at end of file
+}));