added is_really_writable() to Common.php, replaced is_writable() throughout application with is_really_writable()
diff --git a/system/libraries/Output.php b/system/libraries/Output.php
index f98dab5..a4d8d34 100644
--- a/system/libraries/Output.php
+++ b/system/libraries/Output.php
@@ -285,7 +285,7 @@
 	

 		$cache_path = ($path == '') ? BASEPATH.'cache/' : $path;

 		

-		if ( ! is_dir($cache_path) OR ! is_writable($cache_path))

+		if ( ! is_dir($cache_path) OR ! is_really_writable($cache_path))

 		{

 			return;

 		}

@@ -327,7 +327,7 @@
 	

 		$cache_path = ($CFG->item('cache_path') == '') ? BASEPATH.'cache/' : $CFG->item('cache_path');

 			

-		if ( ! is_dir($cache_path) OR ! is_writable($cache_path))

+		if ( ! is_dir($cache_path) OR ! is_really_writable($cache_path))

 		{

 			return FALSE;

 		}