var changed = 0;

function upscroll(thispos, thiscont) {
if (eval(thispos) < 0) {
var tempo = eval(thispos);
tempo += 30;
changed = 30;
document.getElementById(thiscont).style.top = tempo+'px';
} else{
changed = 0;
}


}


function downscroll(thispos, thiscont) {
   if (document.layers) {  
      hoehe = document.getElementById(thiscont).document.height;
   }
   else {
     hoehe = document.getElementById(thiscont).offsetHeight;
   }
   
   if (eval(thispos) > (eval(-hoehe)+90)) {
var tempo = eval(thispos);
tempo -= 30;
changed = -30;
document.getElementById(thiscont).style.top = tempo+'px';
} else{
changed = 0;
}
   
}