Calling Card Ecommerce

I am in need of a simple shopping cart for selling voip services - This will be hosted VOIP services - some given plans - calling plans. Client will select the calling card as per his destination country search. Once client pays for services - access to the backend control panel will be given and mailed to his mail id. I next need the control panel for clients to login. This control panel will display the clients current balance - give the ability to add credit - and to show call detail records from a existing database. Applicatin developed will pull the data from database and will need a sub admin section of the control panel so the call plans can be set per client and editable. There will need to be client auto-replenishment and notifications on low balances. There might be some other minor needs not addressed here as the project gets completed and I can see the functionality come to life. Service providers who are interested in ongoing work from this project are encouraged. I am not looking for a company to perform the work and walk away. This project will need to be modular and ready to increase options as needed. We are looking for a web site similar to [login to view URL], [login to view URL], I am interested in someone that could be apart of this project.