OJS has rudimentary LDAP support, but aside from that, no integration or SSO work has been done yet. You might want to read the thread at http://pkp.sfu.ca/support/forum/viewtopic.php?f=8&t=2322
and/or contact the user to see if you can join forces, if you're interested in working on SSO. OJS has custom session-handling code that should be easy to extend or override if you're handy with PHP.
This is definitely something we're interested in working on in the future, as OJS deploys well as part of a combined package including e.g. a CMS (like Drupal) and a Wiki (like MediaWiki), but it hasn't been a high priority for us yet.
Public Knowledge Project Team