My contact numbers are 8 digits which are fine for dialing from the iphone, but my zoiper SIP account requieres a 9 before dialing the 8 digits to get an outside line. I need to have zoiper only add the 9 prefix for all my contact numbers. How do I accomplish this? I tried using the 9 as a prefix character but it also requiers me to select a country code (in my case Guatemala 502), so as I do not have the 502 on my contact numbers, zoiper adds 9 and 502 to the number instead of only the 9. Thank you