Can you explain what you mean by Confluence being certified for Mac? If you mean supported on Mac server, the answer is no, as per the Supported Platforms that Jason pasted above. However, the link should be this one, for Confluence 5.6.3: https://confluence.atlassian.com/display/CONF56/Supported+Platforms
If that's not exactly what you want to know, please let us know so we can help you.
Do you use templates with Confluence? Take part in a remote 1-hr workshop. You'll receive USD $100 for your time! We're looking for people to participate in a remote 1-hr workshop...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs