asterisk users - May 2004 - Please help the new guy (the s extension)

This may have been in the archives but I didn't see it. I have a new * setup
with the demo loaded and ready to go. when I dial in, I get "extension (my
*
number) in context default from (calling number) does not exist" and it
denies the call. this is trying to use the "s" extension (default demo
extensions). if I configure an extension for my * 10 digit number it works
fine. I am using 2 PRIs in a trunk group with one phone number. everything
is default except for zaptel.conf and zapata.conf which I used to set up the
PRIs. can anyone help me with this. sorry if I sound stupid but this is my
first day with Asterisk.