billing software

We are looking for a billing software similar to perlbill, with all the features and functions listed [login to view URL] Gateway support for PayPal, NoChex, WorldPay, [login to view URL] and 2Checkout with support for preCharge Client Area - The user area is where your clients place orders and login to their accounts to submit support requests or view invoices/services. Staff Area - The staff area for technical/sales/support staff to login and respond to user inquiries, which were submitted via email or the client help desk. Staff members can be limited to certain departments. Administration - The admin area is where you can manage clients, approve new clients and update invoices etc. Scripting should provide an automated install, mysql based, perl or php and the ability to add and remove modules and full support files, faq and documentation. Full documentation on how to create modules must be included.