diff --git a/app/assets/javascripts/external/Markdown.Converter.js b/app/assets/javascripts/external/Markdown.Converter.js
index 13c601e08..5ae53d317 100644
--- a/app/assets/javascripts/external/Markdown.Converter.js
+++ b/app/assets/javascripts/external/Markdown.Converter.js
@@ -1274,9 +1274,12 @@ else
 
             //  autolink anything like <http://example.com>
             
-            var replacer = function (wholematch, m1) { return "<a href=\"" + m1 + "\">" + pluginHooks.plainLinkText(m1) + "</a>"; }
+            var replacer = function (wholematch, m1) { 
+                m1encoded = m1.replace(/\_\_/, '%5F%5F');
+                return "<a href=\"" + m1encoded + "\">" + pluginHooks.plainLinkText(m1) + "</a>"; 
+            }
             text = text.replace(/<((https?|ftp):[^'">\s]+)>/gi, replacer);
-
+            
             return text;
         }