var image_name = null
if(document.images){

//home

home_icon		= new Image();
home_icon.src		= "icons/home_icon.jpg";
home_icon_over		= new Image();
home_icon_over.src	= "icons/home_icon_over.jpg";


//about

about_icon		= new Image();
about_icon.src		= "icons/about_icon.jpg";
about_icon_over		= new Image();
about_icon_over.src	= "icons/about_icon_over.jpg";

//placeanad

placeanad_icon		= new Image();
placeanad_icon.src		= "icons/placeanad_icon.jpg";
placeanad_icon_over		= new Image();
placeanad_icon_over.src	= "icons/placeanad_icon_over.jpg";


//contact

contact_icon		= new Image();
contact_icon.src	= "icons/contact_icon.jpg";
contact_icon_over	= new Image();
contact_icon_over.src	= "icons/contact_icon_over.jpg";


}

function change_over(image_name)
{
if (document.images){

if (image_name == "home_icon") document[image_name].src = home_icon_over.src ;
if (image_name == "about_icon") document[image_name].src = about_icon_over.src ;
if (image_name == "placeanad_icon") document[image_name].src = placeanad_icon_over.src ;
if (image_name == "contact_icon") document[image_name].src = contact_icon_over.src ;



}
}

function change_back(image_name)
{
if (document.images){

if (image_name == "home_icon") document[image_name].src = home_icon.src ;
if (image_name == "about_icon") document[image_name].src = about_icon.src ;
if (image_name == "placeanad_icon") document[image_name].src = placeanad_icon.src ;
if (image_name == "contact_icon") document[image_name].src = contact_icon.src ;


}
}