Do anybody know any open sorce of a prepaid or calling card application for ser??

Thanks & Regards
Ritesh Jalan
Senior Engineer - Test & Audit
Net4india Ltd.
703, Bhikaji Cama Bhawan
11, Bhikaji Cama Place
New Delhi 110066
Tel: 91 (011) (26160129 - 131) (Extn 131)
URL: http://www.net4india.com