Something like this will work:
Then, com.foo.SomeController will have a setTheirsRemoteObject(TheirsRemoteObject obj) method, and com.foo.RemoteFactory will have a static TheirsRemoteObject getTheirsRemoteObject() method. (Theirs remote object should probably be an interface, though this is not a requirement).
<bean id="myController" class="com.foo.SomeController">
<bean factory-method="getTheirsRemoteObjectInstance" class="com.foo.RemoteFactory" />
I almost didn't think it would work because the SpringIDE plugin complains about the inner bean: "factory-method" must be declared for element type "bean". But it works at runtime.