function WriteAddressLink(display, nickname, username, domain, extra) {
  if (extra == undefined) {
    document.write('<a href=\"mailto:' + nickname + ' \&lt;' + username + '@');
    document.write(domain + '\&gt; \">'); 
  }
  else {
    document.write('<a href=\"mailto:' + nickname + ' \&lt;' + username + '@');
    document.write(domain + '\&gt; ' + extra + '\">'); 
  }
  document.write(display + '<\/a>');
}