function validate() 
{
	if (document.contactus.yname.value.length==0)
	{
		alert("please enter your name");
		document.contactus.yname.focus();
		return false;
	}
	if (document.contactus.address.value.length==0)
	{
		alert("please enter address");
		document.contactus.address.focus();
		return false;
	}
	if (document.contactus.emailadd.value.length==0)
	{
		alert("please enter email address");
		document.contactus.emailadd.focus();
		return false;
	}
	if(!nvalidateEmail(document.contactus.emailadd.value)) 
    { 
    	alert("please enter your valid email address"); 
		document.contactus.emailadd.focus();
        return false; 
    }
	if (document.contactus.phone.value.length==0)
	{
		alert("please enter phone number");
		document.contactus.phone.focus();
		return false;
	}
	return true;
}
function nvalidateEmail(email)
{
    var splitted = email.match("^(.+)@(.+)$");
    if(splitted == null) return false;
    if(splitted[1] != null )
    {
      var regexp_user=/^\"?[\w-_\.]*\"?$/;
      if(splitted[1].match(regexp_user) == null) return false;
    }
    if(splitted[2] != null)
    {
      var regexp_domain=/^[\w-\.]*\.[A-Za-z]{2,4}$/;
      if(splitted[2].match(regexp_domain) == null) 
      {
	    var regexp_ip =/^\[\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\]$/;
	    if(splitted[2].match(regexp_ip) == null) return false;
      }// if
      return true;
    }
}