diff --git a/drivers/isdn/i4l/isdn_tty.c b/drivers/isdn/i4l/isdn_tty.c
index ea5f30d4a5a2..4e5f87c1e714 100644
--- a/drivers/isdn/i4l/isdn_tty.c
+++ b/drivers/isdn/i4l/isdn_tty.c
@@ -2693,8 +2693,9 @@ isdn_tty_getdial(char *p, char *q,int cnt)
 	int limit = ISDN_MSNLEN - 1;	/* MUST match the size of interface var to avoid
 					buffer overflow */
 
-	while (strchr(" 0123456789,#.*WPTS-", *p) && *p && --cnt>0) {
+	while (strchr(" 0123456789,#.*WPTSR-", *p) && *p && --cnt>0) {
 		if ((*p >= '0' && *p <= '9') || ((*p == 'S') && first) ||
+		    ((*p == 'R') && first) ||
 		    (*p == '*') || (*p == '#')) {
 			*q++ = *p;
 			limit--;