if (document.images) {
  var pum1  = new Image();
  var pum2  = new Image();

  var pum3  = new Image();
  var pum4  = new Image();

  var pum5  = new Image();
  var pum6  = new Image();

  var pum7  = new Image();
  var pum8  = new Image();

  var pum9  = new Image();
  var pum10 = new Image();

  var pum11 = new Image();
  var pum12 = new Image();

  var pum13 = new Image();
  var pum14 = new Image();

  var pum15 = new Image();
  var pum16 = new Image();

  var pum17 = new Image();
  var pum18 = new Image();
  
  var pum24 = new Image();
  var pum25 = new Image();

  pum1.src  = "images/toolbar_buttons/home.gif";
  pum2.src  = "images/toolbar_buttons/home_o.gif";
  pum3.src  = "images/toolbar_buttons/about.gif";  
  pum4.src  = "images/toolbar_buttons/about_o.gif";
  pum5.src  = "images/toolbar_buttons/contact.gif";
  pum6.src  = "images/toolbar_buttons/contact_o.gif";
  pum7.src  = "images/toolbar_buttons/news.gif";
  pum8.src  = "images/toolbar_buttons/news_o.gif";
  pum9.src  = "images/toolbar_buttons/production.gif";
  pum10.src = "images/toolbar_buttons/production_o.gif";
  pum11.src = "images/toolbar_buttons/epublishing.gif";
  pum12.src = "images/toolbar_buttons/epublishing_o.gif";
  pum13.src = "images/toolbar_buttons/samples.gif";
  pum14.src = "images/toolbar_buttons/samples_o.gif";
  pum15.src = "images/toolbar_buttons/support.gif";
  pum16.src = "images/toolbar_buttons/support_o.gif";
  pum17.src = "images/toolbar_buttons/recent.gif";
  pum18.src = "images/toolbar_buttons/recent_o.gif";
  pum24.src = "images/toolbar_buttons/employment.gif";
  pum25.src = "images/toolbar_buttons/employment_o.gif";
}

function hide_home() {
	if (document.images) {
		document["pum"].src = pum1.src;
	}
}	
function show_home() {
	if (document.images) {
		document["pum"].src = pum2.src;
	}
}


function hide_about() {
	if (document.images) {
		document["paum"].src = pum3.src;
	}
}	
function show_about() {
	if (document.images) {
		document["paum"].src = pum4.src;
	}
}


function hide_contact() {
	if (document.images) {
		document["pcum"].src = pum5.src;
	}
}	
function show_contact() {
	if (document.images) {
		document["pcum"].src = pum6.src;
	}
}

function hide_news() {
	if (document.images) {
		document["pnum"].src = pum7.src;
	}
}	
function show_news() {
	if (document.images) {
		document["pnum"].src = pum8.src;
	}
}

function hide_production() {
	if (document.images) {
		document["ppum"].src = pum9.src;
	}
}	
function show_production() {
	if (document.images) {
		document["ppum"].src = pum10.src;
	}
}

function hide_epublishing() {
	if (document.images) {
		document["peum"].src = pum11.src;
	}
}	
function show_epublishing() {
	if (document.images) {
		document["peum"].src = pum12.src;
	}
}

function hide_samples() {
	if (document.images) {
		document["psaum"].src = pum13.src;
	}
}	
function show_samples() {
	if (document.images) {
		document["psaum"].src = pum14.src;
	}
}

function hide_support() {
	if (document.images) {
		document["psum"].src = pum15.src;
	}
}	
function show_support() {
	if (document.images) {
		document["psum"].src = pum16.src;
	}
}

function hide_recent() {
	if (document.images) {
		document["prum"].src = pum17.src;
	}
}
function show_recent() {
	if (document.images) {
		document["prum"].src = pum18.src;
	}
}

function hide_employment() {
	if (document.images) {
		document["pemployment"].src = pum24.src;
	}
}
function show_employment() {
	if (document.images) {
		document["pemployment"].src = pum25.src;
	}
}


if (document.images) {
   var pum21 = new Image();
   var pum22 = new Image();
   var pum23 = new Image();
   var pum30 = new Image();
   var pum31 = new Image();
   var pum32 = new Image();
   var pum27 = new Image();
   var pum28 = new Image();
   var pum29 = new Image();
   
   pum21.src = "images/page_buttons/top-up.gif";
   pum22.src = "images/page_buttons/top-over.gif";
   pum23.src = "images/page_buttons/top-down.gif";
   pum30.src = "images/page_buttons/next1-up.gif";
   pum31.src = "images/page_buttons/next1-over.gif";
   pum32.src = "images/page_buttons/next1-down.gif";
   pum27.src = "images/page_buttons/previous-up.gif";
   pum28.src = "images/page_buttons/previous-over.gif";
   pum29.src = "images/page_buttons/previous-down.gif";
   
   
}

function show_rock() {
	if (document.images) {
		document["plum"].src = pum22.src;
	}
}

function hide_rock() {
	if (document.images) {
		document["plum"].src = pum21.src;
	}
}	

function down_rock() {
	if (document.images) {
		document["plum"].src = pum23.src;
	}
}


function show_recent2() {
	if (document.images) {
		document["plum2"].src = pum30.src;
	}
}

function hide_recent2() {
	if (document.images) {
		document["plum2"].src = pum31.src;
	}
}	

function down_recent2() {
	if (document.images) {
		document["plum2"].src = pum32.src;
	}
}
function show_recent1() {
	if (document.images) {
		document["plum1"].src = pum27.src;
	}
}

function hide_recent1() {
	if (document.images) {
		document["plum1"].src = pum28.src;
	}
}	

function down_recent1() {
	if (document.images) {
		document["plum1"].src = pum29.src;
	}
}