function setMailLink(An, Dn, En) { 
	var LinkText = An + "@" + Dn + "." + En; 
	document.open(); 
	document.write("<a href=\"mailto:" + LinkText + "\">" + LinkText + "</a>"); 
	document.close(); 
}

//Aufruf

//<script type="text/javascript">setMailLink('meier','web','de');</script>