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?

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

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.

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