One thing that it doesn't support however is multiple websites defined within IIS. Well, that's what the paperwork says !
As there isn't an 'official' option to run Win-Server2K3 on VirtualPC yet, there had to be a way round the problem...
Well, there is....
To create a new website you need to kick off the Command Prompt and change to the IIS Admin Scripts directory
then enter the following to copy the current site
cscript adsutil.vbs COPY W3SVC/1 W3SVC/2
note #1: it doesn't matter what port or IP address you attach to... only one can be started at a time
note #2: you'll need to change the "W3SVC/2" as appropriate.
To delete a specific instance enter the following;
adsutil.vbs delete W3SVC/2
note #3: As in note #2 above, remember to change the "W3SVC/2" as appropriate.