gnutls. You can easily upgrade a Debian system by adding the following
to `/etc/apt/sources.list.d/monkeysphere.list`:
- deb http://monkeysphere.info/debian experimental gnutls
- deb-src http://monkeysphere.info/debian experimental gnutls
+ deb http://archive.monkeysphere.info/debian experimental gnutls
+ deb-src http://archive.monkeysphere.info/debian experimental gnutls
Next, run `aptitude update; aptitude install libgnutls26`.