function validate_form(callbackform)
	{

    var fvalid=true;

 	 if (callbackform.name.value=='') {
    	fvalid=false;
    	alert('Please enter a Name.');
  	}
	else
  	if (callbackform.tel.value=='') {
   		fvalid=false;
    	alert('Please enter a Telephone no.');
  	}
	else
	if (callbackform.email.value == "")
    {
		fvalid=false;
    	alert('You must include an accurate email address for a response.');
  	}
	else
  	if ((callbackform.email.value.indexOf ('@',0) == -1 ||
   		callbackform.email.value.indexOf ('.',0) == -1) &&
   		callbackform.email.value != "")
  	{
		fvalid=false;
    	alert('Please verify that your email address is valid.');
  	} 
	
  	if (fvalid==true) {
  		return true;
  	} 
	else 
	{
        return false;
    }
}