PIX 501 Port forwarding

Hi,

I have a client who has installed a PIX 501. The client was given just
one ip address which has been configuered as the outside interface.
The end result is they want to forward http traffic to a Web server
within. PAT is configured via:

global (outside) 1 interface
nat (inside) 1 0.0.0.0 0.0.0.0 0 0

The problem is that it appears one cannot static the outside interface
to a local address (I assume this is true from the config examples I
have seen on the Web.) I have also witnessed my ssh connection drop
when I try ;-) On a cheap Linksys (etc.) this is trivial. Do I really
need two routable ip addresses so that one can be the outside
interface on the PIX and the other ip map to an inside address?

Thanks!

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