IIS Limitations???

Hello,

I am running IIS on a Windows XP Professional system. I have installed all IIS components including Front Page Server Extensions, FTP Services, SMTP Services, Internet Services Manager, etc. The problem is when I try to add a second web site the option is unavailable, there isn?t even an option to add anything. The option to add a new Web Site and FTP Site was available on a Windows Server OS which was pre-installed. I have been perusing through Microsoft references but I found nothing?is there a component that I am missing or a limitation on the number of web sites on a workstation compared to a server OS I am unaware of?

Thanks for your time,

Tyler