var butAct = 99; // indicate the button with the active state, 99 => no button is active
         var docAct = null;
         var browserVersion=0;
         var browserVersion=0;

         if (navigator.userAgent.indexOf("Mozilla/5") != -1)
            browserVersion = 4;
         else if (navigator.userAgent.indexOf("Mozilla/4") != -1)
            browserVersion = 4;
         else if (navigator.userAgent.indexOf("Mozilla/3.0") != -1)
            browserVersion = 3;
         else if (navigator.userAgent.indexOf("Mozilla/2.0") != -1)
            browserVersion = 2;
         else if (navigator.userAgent.indexOf("MSIE") != -1)
            browserVersion = 1;