diff --git a/source/Ox.UI/js/Core/URL.js b/source/Ox.UI/js/Core/URL.js
index 97e4fe77..a9662da5 100644
--- a/source/Ox.UI/js/Core/URL.js
+++ b/source/Ox.UI/js/Core/URL.js
@@ -563,7 +563,7 @@ Ox.URL = function(options) {
     }
 
     function decodeValue(value) {
-        return Ox.decodeURIComponent(value);
+        return Ox.decodeURIComponent(value).replace(/_/g, ' ').replace(Ox.char(9), '_');
     }
 
     function encodeValue(value) {
@@ -576,7 +576,7 @@ Ox.URL = function(options) {
                 ? '%' + char.charCodeAt(0).toString(16).toUpperCase()
                 : char;
         });
-        return ret;
+        return ret.replace(/_/g, '%09').replace(/\s/g, '_');
     }
 
     function isNumericalSpan(str) {