problema con javascript

[marcoberrios10]

function clipLayer(name, clipleft, cliptop, clipright, clipbottom) {
var layer = getLayer(name);
if (layer != null) {
if (isNav4) {
layer.clip.left = clipleft;
layer.clip.top = cliptop;
layer.clip.right = clipright;
layer.clip.bottom = clipbottom;
} else if (isIE && is5up) {
layer.clip = 'rect(' + cliptop + ' ' + clipright + ' ' + clipbottom + ' ' + clipleft +')';
} else if(isIE && is8up){
layer.clip = 'rect(' + cliptop + ', ' + clipright + ', ' + clipbottom + ', ' + clipleft +')';
}else {
layer.height = clipbottom - cliptop;
layer.width = clipright - clipleft;
layer.top = (cliptop+vspc) + "px";
layer.left = (clipleft+hspc) + "px";
}
}
}

// me dice en el sitio web que la la "vspc" no esta definida
//