Hi, I have to restrict the user from signing twice to my site from the same place or from another place. I would like you give functionality similar to Yahoo/MSN messenger, when the user logs in for the second time. In my applicatin I am able to catch the user when he logs in second time, and giving a message to the user about the relogin. But I want to close the previous session of the user, so that the user can continue working at this place. Any ideas/advices on how to do this.