function validate_gift_aid() {

	if (document.ga_form.first_name.value==""){
		alert("Your first name required");
		document.ga_form.first_name.focus();
		return false;
	}

	else if (document.ga_form.last_name.value==""){
		alert("Your last name required");
		document.ga_form.last_name.focus();
		return false;
	}

	else if (document.ga_form.address.value==""){
		alert("Your address required");
		document.ga_form.address.focus();
		return false;
	}

	else if (document.ga_form.postcode.value==""){
		alert("Your post code required");
		document.ga_form.postcode.focus();
		return false;
	}

	if ((document.ga_form.email)&&((document.ga_form.email.value=="")||(document.ga_form.email.value=="email"))){
		alert("Please enter your e-mail address ...");
		document.ga_form.email.value="";
		document.ga_form.email.focus();
		return false;
	} else {
		return isGAReady();
	}
	
	return true;

}
			 
function isGAReady() {
	if (isGAEmail(document.ga_form.email.value) == false) {
		alert("Please enter a valid email address");
		document.ga_form.email.focus();
		return false;
	}
	return true;
}

function isGAEmail(string) {
	if (string.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1){
		return true;
	}
	else {
		return false;
	}
}