title: verify login credentials for external site
body: <p>I have a website that asks a user for his login credentials for a different site. This site is external to my server. Something like craigslist.com. After the user provides me with his username and password I want to be able to verify that these credentials are valid for that site, otherwise I want to let the user know that he incorrectly entered the credentials for the external site. Is there a way for me to do this? I would prefer if the solution was in asp.net(vb.net/aspx) but, i'm willing to work with other languages. I'll find a way to make them communicate if I have to.</p>