Microsoft Projtool application login as someone else.HELP

Question

I have been pulling my hair out with this one. With projtool(found in the sample code of http://www.microsoft.com/downloads/details.aspx?familyid=2672f6f9-7028-4b30-99a2-18cb1eed1abe&displaylang=en) you can login to HTTP://Servername/PWA with the windows radio button checked. Is there anyway i can login as someone else other then my default windows credentials? No matter what i try to pass wheather it be mysettings.username or anything it always logs in as \\mydomain\usernamehere . Anyone that can point me in the right direction would be greatly appreciated