function AOA_SelectMultiple(id)
{
	this.id = id;
	this.selectElement = document.getElementById(id);
	this.aPreviousSelected = new Array();
	this.aSelected = new Array();
	this.lastSelectedValue;
	this.fetchSelected();
}

AOA_SelectMultiple.prototype.fetchSelected = function()
{
	this.aSelected = new Array();
	if (this.selectElement.options.length > 0) {
		for (var i = 0; i < this.selectElement.options.length; i++) {
			if (this.selectElement.options[i].selected) {
				this.aSelected.push(this.selectElement.options[i].value);
			}
		}
	}
};

AOA_SelectMultiple.prototype.getLastSelectedValue = function()
{
	for (var i = 0; i < this.aSelected.length; i++) {
		if (this.aPreviousSelected.indexOf(this.aSelected[i]) == -1) {
			this.lastSelectedValue = this.aSelected[i];
		}
	}
	this.aPreviousSelected = this.aSelected;
	
	return this.lastSelectedValue;
};