Connecting to a PostgreSQL Server remotely

Hi!  I had a few questions.  I've postgresql 8.1 setup on a desktop  
which is occasionally behind a VPN, running a server.  I've a laptop  
running 8.1 as well, with which I'd like to be able to access the  
server.  I've attempted to change the listen_addresses parameter to  
'*' and then reloaded with pg_ctl reload; however, I still get a  
"server doesn't listen" error.  I'm using pgAdmin III, and I was  
hoping someone might be able to help me out?

Thanks a bunch!

Gratefully,
a.