Claude,
The Spring Framework of course allows your application in any container or server environment. The only difference is how you will access the Spring context. So for instance you are probably familiar with ApplicationContext or GenericApplicationContext as you are currently operating within a stand alone server mode application.
When working within a web environment you will deal with the WebApplicationContext ( a decendent of ApplicationContext), while having set it up within your web.xml file. There are a number of ways to do this, with the most straightforward one being to configure Spring's DispatcherServlet that will also get hooked up with your configuration XML, or if you prefer JavaConfig style @Configuration scanning.
All of the supported remoting technologies (RMI, HTTP, JMS, ETC...) will be available through Spring in whatever environmentyour application is in. You can even setup Hessian endpoints with ease. They are fast, cross-platform, and transmit in binary.
You should finally visit the well written Spring reference manual for more details. here is a link to the remoting section:
http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/remoting.html
I hope this helps your decision making process. And let us know if you have any more questions!
Thanks,
Mario