//This function changes tabs and content
  function change_tab($sender,$target_id){
  	
  	var $target = document.getElementById($target_id);
  	
	//Direct reference to parent <ul> tag
	var $sender_parent = $sender.parentNode;
	
	//Get number of tabs present
	var $number_of_tabs = $sender.parentNode.childNodes.length;
	
	//Loop through and set each tab to its undecorated state
	for(var $i=0; $i < ($number_of_tabs); $i++)
	{
		$sender.parentNode.childNodes[$i].className = "";
	}
	
	//Then set the active tab to ... well ... active
	$sender.className = "current";
	
	//Array of content ids
	var $array_of_content_ids = new Array("overview", "webapp", "digitizing", "consulting", "southwest", "gulfcoast", "rockies", "mid-continent");
	
	//loop through and hide all the content
	for(var $i=0; $i < ($array_of_content_ids.length); $i++)
	{
		if(document.getElementById($array_of_content_ids[$i]))
		{
			document.getElementById($array_of_content_ids[$i]).style.display = "none";;
		}
	}
	
	//Then show the target content
	$target.style.display = "block";

	return true
  }