Varnish answering multiple incoming ports

[Fredrik Nygren]

Hi,
I've browsed the mail archives but I can't find an answer for this  
question. Please point me to the thread if I've missed something.

I use a hardware load balancer in front of my web environment which  
forward the traffic to my web servers on different ports depending on  
the requested domain. For example:

domain1.com => port 81
domain2.com => port 82
domain3.com => port 83

Because of this I would like Varnish to listen for multiple incoming  
ports. Is it possible? I've tried this with no luck:

# varnish -a localhost:81 -a localhost:82 -a localhost:83

Better suggestions?

Regards
</Fredrik>