Github user svenmeier commented on the issue:
https://github.com/apache/wicket/pull/255
Yes, this is what I came up with yesterday too.
We have to support file inputs in forms too, for that I changed
serializeInput() to handle "file" types.
I'd like to drop support for the old iframe solution in
submitMultipartForm(). I'll create an issue, let's see what other devs are
thinking of this.---
