function trim(str) {
    return str.replace(/^\s\s*/, '').replace(/\s\s*$/, '');
}


function validateForm() 
{
	var valid = true;
	if (trim(document.getElementById('first_name').value) == '') 
	{
		valid = false;
		alert ("Please enter your First Name.");	
		document.getElementById('first_name').value = '';
		document.getElementById('first_name').focus();
	}
	
	if (trim(document.getElementById('last_name').value) == '' && valid) 
	{
		valid = false;
		alert ("Please enter your Last Name.");	
		document.getElementById('last_name').value = '';
		document.getElementById('last_name').focus();
	}
	
	var filter = /^([a-zA-Z0-9_.-])+@(([a-zA-Z0-9-])+.)+([a-zA-Z0-9]{2,4})+$/;
	if (!filter.test(document.getElementById('email').value) && valid)
	{
		valid = false;
		alert('Please provide a valid email address');
		document.getElementById('email').focus();
	}		

	if (valid==true)  
	{
		document.newsletter_form.submit();
		win = window.open("./thanks.html", "", "height=60, width=400"); win.moveTo((screen.width/2)-200,(screen.height/2)-200);		
	} 
}