function pressed_button(v_button_name)  {
    v_submenu_name = "submenu_"+v_button_name.slice(7);
    //window.alert(v_submenu_name);
    oElements = document.getElementsByName(v_button_name);
    oElement = oElements[0];
    oElement.setAttribute("src", "img/"+v_button_name+"_pressed.gif"); 

    if ((v_submenu_name == "submenu_nomi") || (v_submenu_name == "submenu_toishi")) {
      if (Element.visible(v_submenu_name) == true) {
        Element.hide(v_submenu_name);
      } else {
        Element.show(v_submenu_name);
      }
      if (v_submenu_name != "submenu_nomi") {
 	    Element.hide("submenu_nomi");
	  } else if (v_submenu_name != "submenu_toishi") {
 	      Element.hide("submenu_toishi");
	  }
    }
}
function mouseover_button(v_button_name) {
    // window.alert("On Mouse Over: "+v_button_name); 
    oElements = document.getElementsByName(v_button_name);
    oElement = oElements[0];
    oElement.setAttribute("src", "img/"+v_button_name+"_mouseover.gif"); 
}
function normal_button(v_button_name) {
    // window.alert("On Mouse Out: "+v_button_name); 
    oElements = document.getElementsByName(v_button_name);
    oElement = oElements[0];
    oElement.setAttribute("src", "img/"+v_button_name+".gif"); 
}