Simple SPDY config not working

I've posted this issue in the queue at the Perusio config page on github, but wondered if anyone else has an idea in more general terms of how to get an up to date system to do an NPN handshake?

Github issue

• Ubuntu 12.04 LTS
• Nginx 1.7.12 (upgraded today from Ubuntu mainline/dev PPA)
• OpenSSL 1.0.1 (build from 19/03/15 - upgraded today)

Have restarted Dovecot/Postfix/PHP5-FPM/Monit and of course Nginx. Spdycheck.org is showing no spdy due to no NPN (but this version of openssl supports it, checked changelog), the Chrome/FF extensions also reporting no spdy. SSL Labs are reporting 'No' for NPN.

Have tried adding the 'add_header Alternate ... npn-spdy/3' line to nginx.conf, my enabled config and also to drupal.conf in apps/drupal. Oh, and also trying to get HSTS working with no joy either. Using the line provided in microcache_fcgi.conf.

What am I doing wrong?

EDIT: Have obviously included the listen line as follows in the sites-enabled:

listen 443 ssl spdy default_server;

[server_name, limit_con, log, keepalive_timeout, ssl certs...]

add_header Strict-Transport-Security "max-age=31536000; includeSubDomains";
add_header Alternate-Protocol  443:npn-spdy/3;