function checkFields() {

	

		
	if(document.contactform.email.value == '') {
		alert("Please enter your email address");
		return false;
		}
		
	else if(validate('contactform','email')==false){
		alert('Please enter a valid email address');
      		return false;
      	}

	
	return true;	
		
		
} 


function validate(form_id,email) {
	var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
	var address = document.forms[form_id].elements[email].value;
	if(reg.test(address) == false) {
		alert('Please enter a valid email address');
	return false;
	}
}