function Newsletter_Check() {
	
	var form_submit = false;
	var newsletter_form_mail = document.getElementById("newsletter_mail");
	var newsletter_form_submit = document.getElementById("newsletter_submit");
	var newsletter_submit_response = document.getElementById("newsletter_submit_response");
	
	var reg = new RegExp("A-Z");
	//reg = new RegExp("[A-Z0-9._-]+", "[A-Z0-9.-]+", "[.]+", "[A-Z]{2,4}");
	
	/*function isEmailAddr(str) 
	{
		return str.match(/^[\w-]+(\.[\w-]+)*@([\w-]+\.)+[a-zA-Z]{2,7}$/);
	}*/
	
	if (newsletter_form_mail.value == "") {
		
		newsletter_form_mail.setAttribute("class", "newsletter_mail newsletter_mail_error");
		newsletter_form_submit.setAttribute("class", "newsletter_submit_button_error");
		newsletter_submit_response.setAttribute("class", "newsletter_submit_error");
		
		newsletter_submit_response.innerHTML = "Please insert an eMail-Adress.";
				
		form_submit = false;			
	}
	else {
		if (!reg.exec(newsletter_form_mail.value)) {
			
			form_submit = true;
		
		} else {
			newsletter_form_mail.setAttribute("class", "newsletter_mail newsletter_mail_error");
			newsletter_form_submit.setAttribute("class", "newsletter_submit_button_error");
			newsletter_submit_response.setAttribute("class", "newsletter_submit_error");
			
			newsletter_submit_response.innerHTML = "eMail-Adress is incorrect.";
					
			form_submit = false;			
		}
	}
	
	return form_submit;
}