Can sendmail listen for SMTP on two prots at once?

[User Ernie]

I am trying to work out a roaming solution for clients with notebooks that  
don't like webmail and need to send outgoing emails via one of our SMTP
servers. At the moment I have a POP befor SMTP solution running which works                        
fine except more and more the clients are finding that outbound port 25 in  
the hotels they stay at is blocked. I was trying to come up with a way to   
get sendmail to listen on two ports at once the normal port 25 and a port   
number above 1024 for the roaming users.  

Anyone have an idea how to achive that or another roaming suggestion to
bypass the hotel blocks?

- Ernie.