Last year I spent some time studying blood clotting. You can read the series of postings by clicking on the "Theme" link.
One of the reasons for reading up on this topic was because the creationists were promoting it as another example of something that could not evolve. Micheal Behe was one of those creationists.
The data is now in. Russel Doolittle has been working on the evolution of the clotting cascade and the latest results incorporate the information from the lamprey genome. Suffice to say, Behe's claims have been decisively refuted.
Ian Musgrave has the scoop in an excellent article on Panda's Thumb [Behe vs Lampreys: A modest proposal]. This should put an end to ignorant speculation about the non-evolvability of the blood clotting pathway. Or, to be more precise, it should put an end to such speculation by any intelligent, rational, person.