Securely administrating WordPress when port 443 is unavailable

There’s a known issue that precludes the use of wordpressMU with port numbers. How do you securely administrate wordpress when you can’t use the default port (443)?

Is this possible or does wordpressMU require a unique IP address where port 443 is available for secure administration?

I’m guessing this has been discussed before. Can anyone point me to the documentation that describes this?