$NetBSD$

--- unix/cohtty.c.orig	2003-05-29 02:08:48.000000000 -0400
+++ unix/cohtty.c
@@ -99,7 +99,7 @@ char enable_device[16];			/* this will h
 		 */
 
 		for(z = strlen(sought_tty.tty_device) ; z > 0 ; z--){
-			if(isdigit(sought_tty.tty_device[z])){
+			if(isdigit(BUCHAR(sought_tty.tty_device[z]))){
 				break;
 			}
 		}
