I’m still not entirely sure what your scenario is: are you trying to configure a development environment in XP to point to an existing SSO installation, or are you trying to create a new SSO installation on your dev machine?
From the error message you are receiving, I would suggest that you are trying to acheive the former: connecting to an existing SSO installation. If that is the case, can I suggest that you have a look at the following forum question which appears to answer your question: http://www.webservertalk.com/message174630.html
If this does not answer your question, could you provide more detail as to your problem.