Is there any reason to keep the beep? For anything but server installations this is really annoying, so I would opt for just removing it completely (see attached patch).
Index: sysvinit-2.88dsf/src/dowall.c =================================================================== --- sysvinit-2.88dsf.orig/src/dowall.c 2010-03-19 17:53:57.000000000 +0100 +++ sysvinit-2.88dsf/src/dowall.c 2013-03-09 12:34:24.063049182 +0100 @@ -190,11 +190,11 @@ if (remote) { snprintf(line, sizeof(line), - "\007\r\nRemote broadcast message (%s):\r\n\r\n", + "\r\nRemote broadcast message (%s):\r\n\r\n", date); } else { snprintf(line, sizeof(line), - "\007\r\nBroadcast message from %s@%s %s(%s):\r\n\r\n", + "\r\nBroadcast message from %s@%s %s(%s):\r\n\r\n", user, hostname, tty, date); }