//validation function for registration form
function validateTellUs(email){
	if(document.getElementById('first_name_textbox').value==''){
		alert("Please fill in your name");
		return false
	}
	if(document.getElementById('comment_text_textbox').value==''){
		alert("Please fill in your comment");		
		return false
	}
	if((document.getElementById('age_textbox')) && (document.getElementById('age_textbox').value=='')){
		alert("Please fill in your age");		
		return false
	}
	if(document.getElementById('country_dropdown').value=='--- Please select ---'){
		alert("Please select your country & county");		
		return false
	}
	//if(!validateEmailAddress(email))
	//	return false
	return true;
}


//check that all fields with classname 'required' are filled in
function validate(){
var elems=document.getElementsByTagName('input'); 
for(var i=0;i<elems.length;i++){
	if((elems[i].className=='required')&&(elems[i].value=="")){
		alert("Please fill in all required fields");
		return false;
	}
}
return true;
}


/*** This validation function checks that an email address contains both '@' and '.' **/
function validateEmailAddress(email_address){
var email = document.getElementById(email_address).value;
	if((email.indexOf('@')==-1)||(email.indexOf('.')==-1)){
		alert("Invalid email address");
		return false;
	}
	else
		return true;
}