Linux FTP Server

We need a Linux FTP server with an absolutely bulletproof way for us to control how many user accounts it has. We will distribute versions of it for 50, 100, 250, etc. user accounts. It's OK to base it on an existing small-footprint server. We will charge for this product, so the base code should not be encumbered by any existing license. Since we will charge a price for it based on the number of user accounts it has, it must be impossible for our customers to increase their number of user accounts by any means other than noted below. We must be able to increase the user counts by emailing our customers a new key file, or giving our customers an unlock code over the phone. The server must be able to operate in two login modes: clear text, as well as some standard form of secure login authentication. SSL is not needed, and is not desired. It must REQUIRE the Account parameter for login. It should operate in Passive Mode only. We need an installer capable of easily and quickly installing the Server on all standard Linux platforms with no help from our Tech Support department. It should be idiot-proof. It needs an easy way to change the command port and the passive mode port range. It should be able to use MySQL database and maybe some other common ones. Further updated spec is at [login to view URL] ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows? (depending on the nature? of the deliverables): a)? For web sites or? other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software? installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform All common flavors of Linux