The sequence of events was something like this:

1. A file named Container.java was added to the project and committed
2. It was somehow copied within Subversion to container.java and committed
3. container.java was deleted from svn, while Container.java remains

All of this was done by someone else, on another machine.

Now on my machine, whenever I edit Container.java, it puts an "Outdated version" banner on the file, and the commit where container.java was deleted stays in my Incoming Changes pane, no matter how many times I update, either within IDEA or from the command-line.