[Javascript] 密碼欄位提示文字"password"

SCRIPT:
script language="javascript">
 function changeBox()
 {
    document.getElementById('div1').style.display='none';
    document.getElementById('div2').style.display='';
    document.getElementById('password').focus();
 }
 function restoreBox()
 {
    if(document.getElementById('password').value=='')
    {
      document.getElementById('div1').style.display='';
      document.getElementById('div2').style.display='none';
    }
 }
/script>

FORM:

div id="div1">
input name="pass_temp" type="text" value="Password" size="20"
maxlength="20" onfocus="changeBox()" />
/div>
div id="div2" style="display:none">
input name="password" id="password" type="password" value="" size="20"
maxlength="20" onBlur="restoreBox()" />
/div>