It seems they are now supported by IE judging from this page <a href="http://www.startssl.com/?app=40" rel="nofollow">http://www.startssl.com/?app=40</a> which show icons of all the major browsers incl. IE but excl. Opera, and this page <a href="http://www.startssl.com/?app=22" rel="nofollow">http://www.startssl.com/?app=22</a> which has the following text redacted (overstrike): <i>Startcom’s certificate isn’t trusted by the Microsoft Internet Explorer</i>.<p>So I think that it is now supported by IE, question is, which version of IE and/or Windows. I can’t find any details about this on the StartSSL’s pages (there used to be a FAQ entry iirc with browsers supported which included version and OS).