function checkform(f)
{
	if (f.ContactName.value == "")
	{
		alert("Please enter your name");
		f.ContactName.focus();
		return false;
	}
	if (f.Telephone.value == ""  &&  f.EmailAddress.value == "")
	{
		alert("Please enter a telephone number or email address");
		f.EmailAddress.focus();
		return false;
	}
	if (f.Enquiry.value == "")
	{
		alert("Please enter an enquiry");
		f.Enquiry.focus();
		return false;
	}
}