// JavaScript Document
function checkElement(elementName){
		if (document.getElementById(elementName).value == '')
		{
			errorMessage = elementName + ' cannot be blank!\n';
		}
		else
		{
			errorMessage = '';
		}
		
		return(errorMessage);
		
};

function validateFields()
{
	var errorMessage;
	errorMessage = '';
	errorMessage += checkElement('firstname');
	errorMessage += checkElement('surname');
	errorMessage += checkElement('postcode');
	errorMessage += checkElement('email');
	
	if (errorMessage == '')	
		{
			document.compForm.submit();
		}
		else
		{
			alert(errorMessage);
		}
		
		
};

function setCallback(){
document.getElementById(callback).value= true;	
};