[Exim] domainless email server

Hi...
I'm new to exim and looked all over for this one....
maybe someone can help?

I have an IP given to me from my isp....
24.60.35.x
I would like to be able to set this up as a pop server...
I installed exim 3.12 and qpopper installed....
Since I don't have any kind of domain name....
can I even set this up?
I was hoping I could use email addresses like such:
mike@???
(mike being an account on my linux box)
so... I tried to set this up....
I can receive email fine but can't send....
I get a message back from my emailer...saying message is frozen...
say I wanted to send an email to here:
joe@???
I get this error message:
message frozen......
lookup of host "24.60.35.x" failed from smarthost router
I guess I'm asking is it even possible to have an email server without
a domain name? and if so... can someone point me in the right direction
to have allow messages to be sent out properly...?

thanks for your help
Mike