var current_set=1;
var display_set=1; 

function on_inset(inset, display_set)
{
    if (display_set != current_set){
	if (current_set) {
		var block = document.getElementById(inset + '_inset' + current_set);
		block.style.display = "none";
		var page = document.getElementById(inset + '_tab' + current_set);
		page.className = "";
	}
	var block = document.getElementById(inset + '_inset' + display_set); 
	block.style.display = "block";
	var page = document.getElementById(inset + '_tab' + display_set);
	page.className = "act";
	current_set = display_set;
    }
}