function strReplaceAll(str,strFind,strReplace){
    var returnStr = str;
    var start = returnStr.indexOf(strFind);
    while (start>=0)
    {
        returnStr = returnStr.substring(0,start) + strReplace + returnStr.substring(start+strFind.length,returnStr.length);
        start = returnStr.indexOf(strFind,start+strReplace.length);
    }
    return returnStr;
}


function open_window_centered(url,name,newwidth,newheight){
      var pos_x = (screen.availWidth/2) - (newwidth/2);
      var pos_y = (screen.availHeight/2) - (newheight/2);
      url = escape(url);
      url = strReplaceAll(url,"+"," ");
      url = strReplaceAll(url,"%3F","?");
      url = strReplaceAll(url,"%3D","=");
      url = strReplaceAll(url,"%26","&");
      cntwindow=window.open(url,name,'status=0, resize=no, height='+newheight+', width='+newwidth+',left='+pos_x+',top='+pos_y);
      cntwindow.focus();
}