MockHttpServletRequest.getHeaders(String header) throws NullPointerException instead of returning an iterator over an empty list, if a header of the given name doesn't exist.
This has worked in Seam 2.0.2, I think.
My usecase: In the process of sending an EMail, a component gets created that has an (optional) injected @RequestParameter. This throws an NPE (which is very difficult to find, since buried deep within other, rather meaningless exceptions).
I would have reported a bug via jira, but the process seamed a bit too complicated to me :-(
