Irvine-based YouMail, the personalized voicemail service run by Alex Quilici, reported today that it has now handled its 500 millionth call. The firm said it is now handling around 1.5 million calls daily on its service. The firm--which is backed by the Tech Coast Angels and VantagePoint Venture Partners--said it also has over one million registered users. YouMail provides both individual users, as well as a number of telephone carriers, with its advanced voicemail services. The firm said IMMIX Wireless in Pennsylvania, Cellular One in East Central Illinois, Blue Wireless in New York, iSmart Mobile in Montana, VoicePulse in New Jersey, and Windy City Cellular in Adak, Alaska area all using the firm's services as their standard voicemail service.