home_on = new Image ( 92, 26 );
home_on.src = "images/bt_home_on.gif";
about_on = new Image ( 92, 26 );
about_on.src = "images/bt_about_on.gif";
virtualtour_on = new Image ( 92, 26 );
virtualtour_on.src = "images/bt_virtualtour_on.gif";
directory_on = new Image ( 92, 26 );
directory_on.src = "images/bt_directory_on.gif";
events_on = new Image ( 92, 26 );
events_on.src = "images/bt_events_on.gif";
contact_on = new Image ( 92, 26 );
contact_on.src = "images/bt_contact_on.gif";

home_off = new Image ( 92, 26 );
home_off.src = "images/bt_home_off.gif";
about_off = new Image ( 92, 26 );
about_off.src = "images/bt_about_off.gif";
virtualtour_off = new Image ( 92, 26 );
virtualtour_off.src = "images/bt_virtualtour_off.gif";
directory_off = new Image ( 92, 26 );
directory_off.src = "images/bt_directory_off.gif";
events_off = new Image ( 92, 26 );
events_off.src = "images/bt_events_off.gif";
contact_off = new Image ( 92, 26 );
contact_off.src = "images/bt_contact_off.gif";

function button_on ( imgName ) {
    butOn = eval ( imgName + "_on.src" );
    document [imgName].src = butOn;
}

function button_off ( imgName ) {
    butOff = eval ( imgName + "_off.src" );
    document [imgName].src = butOff;
}