function highlightCell() {
	
	var getCell = document.getElementById('mailTable').getElementsByTagName('td'); 
	var getCellLength = getCell.length;


	for (i=0; i<getCellLength; i++){
			getCell[i].onmouseover = function() {
					this.className = "cellOver";
			}
			
			getCell[i].onmouseout = function() {
					this.className = "cellOff";
			}			
	}
}