function countdown_clock(year, month, day, hour, minute, format, contador, prova_ok)
         {
         //I chose a div as the container for the timer, but
         //it can be an input tag inside a form, or anything
         //who's displayed content can be changed through
         //client-side scripting.
         html_code = '<div id="' + contador + '"></div>';
         
         document.write(html_code);
         
         Today = new Date();
         Todays_Year = Today.getFullYear() - 2000;
         Todays_Month = Today.getMonth() + 1;
         
                  
         //Computes the time difference between the client computer and the server.
         Server_Date = (new Date(8, 7, 9,
                                 11, 50, 26)).getTime();
         Todays_Date = (new Date(Todays_Year, Todays_Month, Today.getDate(),
                                 Today.getHours(), Today.getMinutes(), Today.getSeconds())).getTime();
         
         countdown(year, month, day, hour, minute, (Todays_Date - Server_Date), format, contador, prova_ok);                
         }
         
function countdown(year, month, day, hour, minute, time_difference, format, contador, prova_ok)
         {
         Today = new Date();
         Todays_Year = Today.getFullYear() - 2000;
         Todays_Month = Today.getMonth() + 1;
                                             
         //Convert today's date and the target date into miliseconds.
         
         Todays_Date = (new Date(Todays_Year, Todays_Month, Today.getDate(),
                                 Today.getHours(), Today.getMinutes(), Today.getSeconds())).getTime();
         Target_Date = (new Date(year, month, day, hour, minute, 00)).getTime();
         
         //Find their difference, and convert that into seconds.
         //Taking into account the time differential between the client computer and the server.
         Time_Left = Math.round((Target_Date - Todays_Date + time_difference) / 1000);
         
         if(Time_Left < 0) {
            Time_Left = Time_Left*(-1);
			Font_tag = '<strong class="cd_atrasado">';
         } else {
			Font_tag = '<strong class="cd_normal">';
		 }
		 
		 if (prova_ok > 0) {
			Font_tag = '<strong class="cd_prova">';
		 }
         switch(format)
               {
               case 0:
                    //The simplest way to display the time left.
                    document.all.countdown.innerHTML = Time_Left + ' seconds';
                    break;
               case 1:
                    //More datailed.
                    days = Math.floor(Time_Left / (60 * 60 * 24));
                    Time_Left %= (60 * 60 * 24);
					
                    hours = Math.floor(Time_Left / (60 * 60));
                    Time_Left %= (60 * 60);
                    minutes = Math.floor(Time_Left / 60);
                    Time_Left %= 60;
                    seconds = Time_Left;
                    
                    if (hours < 10) hours = '0' + hours;
                    if (minutes < 10) minutes = '0' + minutes;
                    if (seconds < 10) seconds = '0' + seconds;
                    //document.all.countdown.innerHTML = days + ' day' + dps + ' ';
					//document.all.countdown.calss = 'teste';
					codigo = 'countdown(' + year + ',' + month + ',' + day + ',' + hour + ',' + minute + ',' + 
                     time_difference + ',' + format + ',\'' + contador + '\', ' + prova_ok + ');';
                    document.getElementById(contador).innerHTML = hours + ':' + minutes + ':' + seconds;
                    break;
               default: 
                    document.getElementById(contador).innerHTML = Time_Left + ' seconds';
               }
               
         //Recursive call, keeps the clock ticking.
         setTimeout(codigo, 1000 );
         }