config.def.h | 1 +

diff --git a/config.def.h b/config.def.h
index dfcbda999eb362ff7d64a2bd14e42d7caebe8d2b..0895a1ff4bd3f00e766891f823248de184ae582f 100644
--- a/config.def.h
+++ b/config.def.h
@@ -18,6 +18,7 @@  * 5: value of shell in config.h
  */
 static char *shell = "/bin/sh";
 char *utmp = NULL;
+/* scroll program: to enable use a string like "scroll" */
 char *scroll = NULL;
 char *stty_args = "stty raw pass8 nl -echo -iexten -cstopb 38400";