passing variable to open a new window

Hi

I got one problem that the page has to load "twice" before the pop-up page open

 protected void Button1_Click(object sender, EventArgs e)
    {
              Button1.Attributes.Add("onclick", "window.open('http://www.megavideo.com/?v=8SR51EET#flashplayer','','height=400,width=500,toolbar=no,location=0,directories=nostatus=no,menubar=no,copyhistory=no,resizable=no,scrollbars=no,toolbar=no,titlebar=no');");

    }

 

 

and I was trying to hide the address bar but failed ......(the tutorial says set loaction to no, but the address bar still shows the "url")

 

any idea?
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