setMaxAge(0) does not work correctly

[Dave Ford]

To delete a cookie called x, the following should work:

Cookie c = new Cookie("x","bla");
c.setMaxAge(0);
response.addCookie(c);

But it doesn't. Upon inspecting the http response header that was actually
generated, I found this:

Set-Cookie: a=18; Path=

I beleive that setMaxAge should result in a value for "expires" perhaps
something like this:

Set-Cookie: a=18; Expires=some_past_date; Path=

Dave Ford