customized bulk sms panel needed

we are looking for a customized bulk sms script to integrate that into our website to sell and buy BULK SMS CREDITS. We want to integrate PAYMENT GATEWAY to process payments. We are looking for a CUSTOMIZED RESELLER PANEL or API to integrate into our website to sell BULK SMS CREDITS. Features Needed: 1. Self user-registration ( in our panel, @present, user-registration is done by ADMINS. we want to let the users able to create their accounts.) 2. increase Character length for a username and password. ( in our panel, @ present, 8 letters.) 3. Mobile Number can be used as a username. 4. After logging into USER ACCOUNT, users can able to BUY sms credits through PAYMENT GATEWAY. ( through debit/credit cards and netbanking) 5. Automatic SMS recharge after online Payment via debit/credit cards.