diff --git a/ChangeLog b/ChangeLog
index 7e52ec02..968082d7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,7 @@
 
 	Fix module loading, #174360.
 	s-s-d now changes group when changing user, #174362.
+	netmask -> CIDR is worked out correctly #174341.
 
 * baselayout-2.0.0_alpha1 (11 Apr 2007)
 
diff --git a/sh/net.sh b/sh/net.sh
index 3f62105b..33b93fcb 100755
--- a/sh/net.sh
+++ b/sh/net.sh
@@ -86,7 +86,7 @@ _netmask2cidr() {
     local IFS=.
     for i in $1; do
 		while [ ${i} != "0" ] ; do
-	    	len=$((${len} + 1))
+	    	len=$((${len} + ${i} % 2))
 	    	i=$((${i} >> 1))
 		done
     done