function equal_cols()
{
	var col_ids = new Array("primary", "secondary", "container");
	var max_ht = 0;
	var n, el, ht;
	for (n in col_ids)
	{
		el = document.getElementById(col_ids[n]);
		ht = el.offsetHeight;
		max_ht = Math.max(ht, max_ht);
	}
	for (n in col_ids)
	{
		el = document.getElementById(col_ids[n]);
		el.style.height = max_ht + "px";
	}
	el = document.getElementById("column_wrapper");
	el.style.height = max_ht + "px";
}