I am developing a flash-based game primarily for desktops, to be hosted on facebook platform (like cityville, sims social etc). The gameplay doesn't involve real-time communication between players unlike an mmorpg. Here each player plays in his own world without any knowledge of other online players. I've written almost 95% of the game logic in actionscript on the client side.
I used Smartfox Server pro on the server side (mostly used for getting data from the DB) and the entire server code is an extension written in java. I'm using json as the protocol for communication.
Although I love smartfox server, as an indie, its tough for me to afford the unlimited users license. Morever its limited just to one machine. So I'm looking for an alternative to smartfox server now.

The reason for choosing smartfox server earlier was to use the server properties supported by it.

Server properties on smartfox server take advantage of the socket connection and are essentially server side objects in java which store some data for the player which he can change frequently during the game. And when he logs out of the game, the extension can write out the final state in the DB (I'm using MySQL). This significantly reduces the number of DB UPDATE/INSERT calls made during the game.

I love the way this works since the data is secure as its on the server side and smartfox server is known to be scalable. (although I'm not sure whether this approach is used widely by gaming industry or not, since this is not an mmorpg, I'm putting all player in the lobby).
So my question is whether any of the free and community supported servers like reddwarf, firebase, BlazeDS etc can provide a similar architecture so that I can use server properties without many code changes?

EDIT : I am not insisting on the exact same feature (thats asking too much!), but atleast a viable messaging system on the server so that I can send actionscript objects from the client using json/binary so that its fast. OR maybe some completely different way to implement what I need here. Thanks in advance.