#354 Hangs when adding feed

[dOb]

When I try to add the feed from
https://addons.mozilla.org/rss/?application=firefox&type=E&list=newest
the progress bar fills but when it's full it starts
over and this continues.

SharpReader gives this error message when trying to
read the feed:
Error reading URL: The underlying connection was
closed: Could not establish trust relationship with
remote server.

The feed works fine with Thunderbird and according to
Feed Validator the feed is valid.