[Zope] How: /foo?var=bar equiv to /foo/bar

I am trying to get rid of those question marks in my urls since it seems to confuse the users but I am not sure really how to do that. I have heard that it can but done but so far I have not found out how it can be done. I want for the last piece of the url to be assigned to the varialbe if a valid object can not by found. I don't really have a problem if this involves python coding I just need a place to start. Thanks