1 files changed, 1 insertions, 1 deletions
diff --git a/railties/html/javascripts/prototype.js b/railties/html/javascripts/prototype.js
index b998985235..5f2f9edb9c 100644
--- a/railties/html/javascripts/prototype.js
+++ b/railties/html/javascripts/prototype.js
@@ -288,7 +288,7 @@ Form.Element.Serializers = {
 
   select: function(element) {
     var index = element.selectedIndex;
-    return [element.name, element.options[index].value];
+    return [element.name, (index >= 0) ? element.options[index].value : ''];
   }
 }