[exim] Need help configuring router and pipe transport

Hey all,
I'm kind of new to exim, and internet mail in general, so be nice
please!

I'm trying to set up a router for a specific local part to go to a pipe
transport and execute a script on my server. I've looked at the FAQ and
docs, but I'm not sure what I'm doing wrong. Here is the error message
I'm getting on my server (names changed to protect the innocent):

2005-03-24 15:51:52 H=server.serverdomain.org mail.serverdomain.org)
[0.0.0.0] F=<jmartens@???> rejected RCPT
<testlocalpart@???>: Unrouteable address

Here's my router:

test_router:
driver = accept
require_files = /usr/local/bin/myScript
local_part = testlocalpart
domains = serverdomain.org
transport = test_transport

And here's my transport:

test_transport:
        driver = pipe
        command = /usr/local/bin/myScript
        current_directory = /tmp
        group = groupname
        home_directory = /tmp
        user = username

So, I'm assuming that the problem is with my router somewhere, but I'm
not sure what it is. Any help would be greatly appreciated.

Thanks,
Jason Martens