function changeButtonRed(name)
{
	var cells=document.getElementsByTagName('img');
	for (var i = 0; i < cells.length; i++)
	{
		if (name == cells[i].name)
		{
			cells[i].src = 'images/red-button.gif';
			break;
		}
	} 
}

function changeButtonYellow(name)
{
	var cells=document.getElementsByTagName('img');
	for (var i = 0; i < cells.length; i++)
	{
		if (name == cells[i].name)
		{
			cells[i].src = 'images/yellow-button.gif';
			break;
		}
	} 
}