Bug#737921: [TLS1.2] gnutls only likes SHA1 and SHA256 certificates

[Tobias Fiebig]

Heho,
the severity of this should be bumped. With hearbleed around the corner
many people are forced to re-issue now. 

With the bug in place this meant that the whole auth-infrastructure in
my setup (around openldap) remains broken. A fix should be pushed as a
security update for libgnutls2.6.

With best Regards,
Tobias