GWT Acegi alternative

I'm starting new project. The client interface is based on GWT (and GXT) I have no say it's predetermined. However I can pick and choose as far as server side so I can have some fun and hopefully learn something new in the process. Some requirements are :

• Exchange with server will be through use of JSON, most if not all of UI will be generated by GWT (JS) on the client, so the client/serve exchange will be limited to data exchange as much 开发者_JAVA百科as possible
• No Hibernate (it's not really supported on the proprietary db I will be connecting to). In the past projects people would use JDBC or iBATIS
• Some sort of IoC (I'm thinking Guice just to stick with Google)
• Some sort of Security framework based on LDAP. In the past we would use Spring security (Acegi) but it wasn't ideal and we had to customize it a lot

So basically should I stick with tried-and-true Spring/Acegi or try something based on Guice? And what that "something" would be and how mature is it?

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Have a look at Apache Shiro. It seems to be gaining ground, with no reference to Spring.

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If you'd like to do IOC on client and server, go with Guice. You can use Guice on the server, and its brother GIN on the client.

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Since nether of the above answers gave me any practical ideas (or almost any) here's formula I ended up with:

Maven + GXT + GWT and Guice + iBaGuice