function Fader(obj,opac) {
  this.obj = obj;
  if( opac != undefined )
  	this.opac = opac;
}

Fader.prototype.setOpac = function(opac) {
	if( opac != undefined )
		this.opac = opac;
	if(is_ie) this.obj.style.filter = 'Alpha(opacity='+this.opac+')';
	if(is_gecko) this.obj.style.opacity = this.opac/100;
}

Fader.prototype.fadeIn = function(handler) {
	var self = this;

	if(this.opac <= 94){
		this.opac+=5;
		this.setOpac();
		setTimeout(function(){self.fadeIn(handler)}, 30);
	}
	else {
		if( handler )
			handler();
	}
}

Fader.prototype.fadeOut = function(handler) {
	var self = this;

	if(this.opac > 0){
		this.opac-=5;
		this.setOpac();
		setTimeout(function(){self.fadeOut(handler)}, 30);
	}
	else {
		if( handler )
			handler();
	}
}

Fader.prototype.noOpac = function() {
	this.setOpac(0);
}

Fader.prototype.fullOpac = function() {
	this.setOpac(100);
}