osCommerce is a very popular application with over 100,000 community members. There are many community contributions which add or modify the standard osCommerce functionality. Many of these contributions can be used in KonaKart (i.e. Country zones) although others, which add database tables and attributes, will not be compatible with the functionality offered by KonaKart.
The aim of KonaKart is to build upon the osCommerce foundation to provide powerful new features such as one page checkout, a comprehensive promotions infrastructure, user definable reports and advanced SEO features in the standard KonaKart offering, for companies requiring a very articulate feature set as well as performance, scalability and maintenance / support .
Only a subset of the osCommerce configuration keys are used by KonaKart and some new ones have been introduced which don't exist in a standard osCommerce installation. A complete list is available here.