diff -ur letterize-1.2.orig/letterize.c letterize-1.2/letterize.c
--- letterize-1.2.orig/letterize.c	1994-10-25 04:29:21.000000000 +0200
+++ letterize-1.2/letterize.c	2008-05-24 13:54:18.000000000 +0300
@@ -18,6 +18,9 @@
 
 		The table is 30 percent populated.
 */
+
+#include <stdio.h>
+
 long obvtab[27][27] =
 {
     {	0X00100001, 0X00040000, 0X00040000, 0X00009000, 0X00808020, 0X00140000,