diff --git a/system/core/Security.php b/system/core/Security.php
index b97df46..15a6643 100755
--- a/system/core/Security.php
+++ b/system/core/Security.php
@@ -573,7 +573,8 @@
 
 		if (is_readable('/dev/urandom') && ($fp = fopen('/dev/urandom', 'rb')) !== FALSE)
 		{
-			stream_set_chunk_size($fp, $length);
+			// Try not to waste entropy ...
+			is_php('5.4') && stream_set_chunk_size($fp, $length);
 			$output = fread($fp, $length);
 			fclose($fp);
 			if ($output !== FALSE)
diff --git a/system/core/compat/password.php b/system/core/compat/password.php
index 60aa578..1f67a52 100644
--- a/system/core/compat/password.php
+++ b/system/core/compat/password.php
@@ -121,7 +121,9 @@
 					return FALSE;
 				}
 
-				stream_set_chunk_size($fp, 16);
+				// Try not to waste entropy ...
+				is_php('5.4') && stream_set_chunk_size($fp, 16);
+
 				$options['salt'] = '';
 				for ($read = 0; $read < 16; $read = ($func_override) ? mb_strlen($options['salt'], '8bit') : strlen($options['salt']))
 				{