[plt-scheme] pretty URLs

hi!

so now i have a blog engine (based on the Continue... tutorial) that can also handle tags of
posts.  i want to use it for different personal projects as a blogfarm engine.  one requirement
for that is that i need something that is i think called "pretty URLs":

http://foo.bar/ --> URL of the blog (i can make this) with links to different tags.

http://foo.bar/baz/ or even better http://baz.foo.bar/ --> URL that makes the same servlet list
the posts tagged "baz".

this is really simple thing but i cannot really imagine how to make it with plt-web-server.  can
somebody point me in the right direction?  i have the vague understanding that there is some
conceptual limitation here that has to do with continuations but i hope it is possible since it's
pretty basic stuff. :)

maxigas