if (document.addEventListener)
{
    document.addEventListener("DOMContentLoaded", ready, false );    
}
else
{
    document.attachEvent("onreadystatechange", function(){
        if ( document.readyState === "complete" ) {
            ready()
        }
    })
}

function addEvent(elem, type, handler)
{
    if (elem.addEventListener)
    {
        elem.addEventListener(type, handler, false);
    } 
    else 
    {
        elem.attachEvent("on"+type, handler);
    }
}

function getElement(ev) 
{
    if (!ev.target) {
        ev.target = ev.srcElement
    }
    return ev.target;
}

function ready()
{
    var user_name=document.getElementById("user_name");
    var user_email=document.getElementById("user_email");
    var user_phone=document.getElementById("user_phone");
    var message=document.getElementById("message");
    
    addEvent(user_name,"focus",setOnFocus(["ваше имя","name"]));
    addEvent(user_email,"focus",setOnFocus(["e-mail","e-mail"]));
    addEvent(user_phone,"focus",setOnFocus(["телефон","phone"])); 
    addEvent(message,"focus",setOnFocus(["текст сообщения","message"])); 
    
    addEvent(message,"blur",setOnBlur(message)); 
    addEvent(user_name,"blur",setOnBlur(user_name));
    addEvent(user_email,"blur",setOnBlur(user_email));
    addEvent(user_phone,"blur",setOnBlur(user_phone));  
}

function setOnFocus (arValue)
{
    return function(){
        var el=getElement(event || window.event);
        if (el.value==arValue[0] || el.value==arValue[1]) {
            el.value='';
        }   
    }
}

function setOnBlur(el)
{
    var val=el.value;
    return function(){
        var element=getElement(event || window.event); 
        if (element.value=='') {
            element.value=val;
        }   
    }
}