Reusing DbContext object created in Spring.Net across controllers and actions

Question

What is better? Or maybe - is the following a good practice? I use Spring.net to create an instance of DbContext and then inject it into every controller for use in actions. The object is a singleton. Sometimes I get an exception which says that the "The ObjectContext instance has been disposed.." I suspect that this might be the reason, however this is not repeatable, and so far my application is only used by me during the development.

Now, would it be better to create a DbContext in every controller class and reuse in it's actions; or maybe create the DbContext object in every action itself; or just set it in the Spring config not to be a singleton, so it is created every time it is being accessed?