Index: includes/common.inc
===================================================================
--- includes/common.inc	(revision 4946)
+++ includes/common.inc	(working copy)
@@ -440,6 +440,7 @@
 
   switch ($uri['scheme']) {
     case 'http':
+    case 'feed':
       $port = isset($uri['port']) ? $uri['port'] : 80;
       $host = $uri['host'] . ($port != 80 ? ':'. $port : '');
       $fp = @fsockopen($uri['host'], $port, $errno, $errstr, 15);
@@ -944,7 +945,7 @@
   if ($absolute) {
     return (bool)preg_match("
       /^                                                      # Start at the beginning of the text
-      (?:ftp|https?):\/\/                                     # Look for ftp, http, or https schemes
+      (?:ftp|https?|feed):\/\/                                # Look for ftp, http, https or feed schemes
       (?:                                                     # Userinfo (optional) which is typically
         (?:(?:[\w\.\-\+!$&'\(\)*\+,;=]|%[0-9a-f]{2})+:)*      # a username or a username and password
         (?:[\w\.\-\+%!$&'\(\)*\+,;=]|%[0-9a-f]{2})+@          # combination