Fix #4005
diff --git a/system/core/URI.php b/system/core/URI.php
index b6eff1f..5b658f6 100644
--- a/system/core/URI.php
+++ b/system/core/URI.php
@@ -203,7 +203,7 @@
 
 		// parse_url() returns false if no host is present, but the path or query string
 		// contains a colon followed by a number
-		$uri = parse_url('dummy'.$_SERVER['REQUEST_URI']);
+		$uri = parse_url('http://dummy'.$_SERVER['REQUEST_URI']);
 		$query = isset($uri['query']) ? $uri['query'] : '';
 		$uri = isset($uri['path']) ? $uri['path'] : '';