--- term-utils/agetty.c
+++ term-utils/agetty.c	2014-02-04 09:33:13.162735763 +0000
@@ -568,6 +568,8 @@ static void login_options_to_argv(char *
 	*argc = i;
 }
 
+#define is_speed(str) (strlen((str)) == strspn((str), "0123456789,"))
+
 /* Parse command-line arguments. */
 static void parse_args(int argc, char **argv, struct options *op)
 {
@@ -746,7 +748,7 @@ static void parse_args(int argc, char **
 	}
 
 	/* Accept "tty", "baudrate tty", and "tty baudrate". */
-	if ('0' <= argv[optind][0] && argv[optind][0] <= '9') {
+	if (is_speed(argv[optind])) {
 		/* Assume BSD style speed. */
 		parse_speeds(op, argv[optind++]);
 		if (argc < optind + 1) {
@@ -758,7 +760,7 @@ static void parse_args(int argc, char **
 		op->tty = argv[optind++];
 		if (argc > optind) {
 			char *v = argv[optind++];
-			if ('0' <= *v && *v <= '9')
+			if (is_speed(v))
 				parse_speeds(op, v);
 			else
 				op->speeds[op->numspeed++] = bcode("9600");