That appears to be standard practice for "model bound" systems where the internal "domain model" is bound directly to the HTTP protocol. You get this issue with ASP.Net MVC as well on most of the trivially implemented projects out there.

This is not really a "framework bug" as such. It's just crap application architecture.

At the core of this issue is a simple misunderstanding on what the "model" part of MVC actually is. The model represents ONLY the request or "form model", not the data model. There should be a mapping of 1:1 between the request and the "form data model" always with no exception. The controller is responsible for translating that into something useful or doing something with it involving the domain/data model.

Unfortunately where the usual CRUD approach is required, ignorance reigns supreme and the shortest path, not the most correct path tends to appear.

I write this as someone who works on a rather large ASP.Net MVC application (100+ controllers) and has seen this many times already.