--- squid.orig	2009-05-31 18:25:04 +0400
+++ squid	2009-05-31 18:07:00 +0400
@@ -51,7 +51,7 @@
 }
 
 tcp_port_mask="^[0-9]+$"
-network_mask="^([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])([.]([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9+]|25[0-5])){3}/([1-9]|[12][0-9]|3[0-1])$"
+network_mask="^([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])([.]([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9+]|25[0-5])){3}(/[1-9]|[12][0-9]|3[0-1])?$"
 
 # initial hacks