Ok, Jeremy, I`ll need a little time to answer - I have 37 pages long specs (Rational Unified format)for the system, but these specs are in Russian for the moment

(the system sold for the first time to the Russian client, so he needed a Russian specs).
I`m fluent in Russian (Russian myself), but anyway I`ll need time to translate all the specs

May be you have some specific questions?
The short description of the system is here:
It`s a Java+JSP+Oracle system, servlet engine is Caucho Resin 2.1 (can be changed, of course), system can handle up to 4 millions users without clustering and a lot more with clustering.
System reaction time must not exceed 4 seconds for the usual operations in the peak time.
Multilingual and template-based interface is supported thru XSL transformation.
System can handle both virtual and offline scratch cards, also it handles usual credit cards, payment proxy can be attached (i.e. the module that supports several payments systems, you can set preferences for the systems (i.e. which system to use first, second, etc), the user will have to input most of the payment info once and this info will be used to post into one system, if the system refuses -into second one and so on).
System can hanlde both services (example: subscriptions) and goods sales.
The scratch card module is only the part of the whole system, which is complex Multi-Level Marketing Accounting system.
I have use-cases diagrams for the system, but I can`t post them here.
Please ask more specific questions, I`ll try to answer them.