HTTPS login certificate warning

When logging in through https://bitbucket.org, I get a warning in both Chrome and FF about the SSL cert. It's been like this for a while, thought I'd mention it.

Text of warning in Chrome...

This is probably not the site you are looking for!

You attempted to reach api.bitbucket.org, but instead you actually reached a server identifying itself as bitbucket.org. This may be caused by a misconfiguration on the server or by something more serious. An attacker on your network could be trying to get you to visit a fake (and potentially harmful) version of api.bitbucket.org. You should not proceed.

Screenshot of FF attached.