A lot of users reported about SSH update issues after removal of Sun SSH from illumos-gate. It had to be transparent for users and silently update SSH to OpenSSH, but due to IPS issue, things has gone wrong, and IPS can crash on this update (Issue 7320). Long-term fix was committed to IPS, but given that it was rebuilt after illumos-gate changes arrived to build server, you can’t easily install new IPS version on old boxes. So, if you see pkg crashing with something like

Action upgrade failed for 'etc/ssh/sshd_config' (pkg://openindiana.org/service/network/ssh):
TypeError: 'NoneType' object is not callable

, edit /etc/ssh/sshd_config (for example, add empty line) and retry updating.