The only way I have found to get RAS to answer on "x" rings is to edit the registry at:
and to locate the modems entry (Usually the 4th entry). Double click to expand it. Locate the modem in question where 0000 is the 1st modem. Double click and highlight the Monitor key. Double click the 1st entry which should be ATS0= and change the number of rings.
You will need to stop and restart the RAS service, but a reboot may be necessary.
See tip tip 394.