I have not experienced any problem configging Ajax4JSF via URL mapping, nor do I imagine there are any problems configging the Seam master servlet via servlet mapping.
Thanks gavin. I'll give it a try.
I have experienced this problem(Ajax4jsf via servlet mapping and Seam via url mapping): All my requestparameters were lost. So no conversation was possible.
When you use consistent mapping(servlet or url) the problem is not present.