diff --git a/Tools/scripts/add-port-to-category-makefile.sh b/Tools/scripts/add-port-to-category-makefile.sh
index 691b21fff996..f77c46b0c90c 100755
--- a/Tools/scripts/add-port-to-category-makefile.sh
+++ b/Tools/scripts/add-port-to-category-makefile.sh
@@ -1,48 +1,50 @@
 #!/bin/sh
 #
 # MAINTAINER: yuri@FreeBSD.org
 
 PORT="$1"
 
 set -e
 set -o pipefail
 
+export LC_ALL=C
+
 ##
 ## add-port-to-category-makefile.sh: adds a new port to {category}/Makefile
 ##
 
 
 # sanity checks
 [ -z "$PORT" ] && echo "this command requires the <port> argument" && exit 1
 (echo "$PORT" | grep -q "/") && echo "port's name can't contain slash" && exit 1
 ! [ -f Makefile ] && echo "no Makefile found, are you in the ports tree?" && exit 1
 ! grep -q "^    SUBDIR += " Makefile && echo "this command can only be run from the ports tree category directory" && exit 1
 ! grep -q "^\\.include <bsd\\.port\\.subdir\\.mk>$" Makefile && echo "this command can only be run from the ports tree category directory" && exit 1
 ! [ -d "$PORT" ] && echo "the '$PORT' directory is missing" && exit 1
 ! [ -f "$PORT/Makefile" ] && echo "'$PORT/Makefile' is missing" && exit 1
 grep -q "^    SUBDIR += $PORT$" Makefile && echo "port '$PORT' is already added" && exit 1
 
 
 # add port to Makefile
 /usr/bin/awk '
 BEGIN {
 	done = 0
 	seen = 0
 	str = "    SUBDIR += '$PORT'"
 }
 /^    SUBDIR \+= / {
 	if (!done && str < $0) {
 		print str
 		done = 1
 	}
 	print $0;
 	seen = seen + 1
 }
 !/^    SUBDIR \+= / {
 	if (seen > 0 && !done) {
 		print str
 		done = 1
 	}
 	print $0
 }' < Makefile > Makefile.new &&
 /bin/mv Makefile.new Makefile