diff --git a/vietnamese/vnconvert/files/patch-vn78.c b/vietnamese/vnconvert/files/patch-vn78.c
new file mode 100644
index 000000000000..ecef42ac3755
--- /dev/null
+++ b/vietnamese/vnconvert/files/patch-vn78.c
@@ -0,0 +1,8 @@
+--- vn78.c.orig	Fri May 20 13:36:15 1994
++++ vn78.c	Sun Mar 25 08:34:01 2001
+@@ -959 +959 @@
+-    for (n = sizeof(icode); n; n--) {
++    for (n = sizeof(icode) - 1; n >= 0; n--) {
+@@ -1004 +1004 @@
+-    for (n = sizeof(icode); n; n--) {
++    for (n = sizeof(icode) - 1; n >= 0; n--) {