Ve Vantage 4 and 8 on the same server?

Our current NT4 server has been rebooting randomly recently and I've
been thinking about moving the installation on to our new 2003 server.
I'm comfortable with the actual installation, but I need to know if I
will be able to install V8 onto the same server.

We'll be doing a parallel changeover period from 4 to 8 which is why
I'd like the 2 versions running simultaneously.