[Plugin: Twit Connect] Login Problem

I have just installed the Twit Connect plugin. I have chosen to use ny own twitter application.
Problem is that when I try to sign in to my website using my twitter account then in the pop up window, I receive this message:

This page is no longer valid. It looks like someone already used the token information you provided. Please return to the site that sent you to this page and try again … it was probably an honest mistake.

Can someone please tell me what could be a reason of this.
You can check it yourself be going on this page and then clicking on “Sign in with Twitter” Button which is present above the comment form.
http://anas.cz.cc/2010/08/20/generate-random-text-in-microsoft-office-word-2003/
Thanks …..