Comment 25 for bug 1069531

Ok, mostly sorted now, it was the account.

Although chat from Google+ was possible when logged into the account in Firefox, the account associated with the non-gmail address started life as a youtube account, hence it had never been connected to a gmail account. This seems to be a requirement, see also:

http://support.google.com/talk/answer/141360?hl=en
http://superuser.com/questions/444262/using-google-talk-with-a-non-apps-non-gmail-google-account

So, added a gmail account, removed it and re-established the non-gmail account as the primary login.
Can now sign in to Empathy properly.

Tested by sending an invite to a second gmail account not already displayed in the G+ chat list of online users. This worked properly and could send message back and forth as expected.

However, as yet all of the existing G+ contacts are showing as offline (which they are not - the second gmail account has a contact that is visible to both accounts and can see that contact fine).

This could be a result of the account having been messed around with, won't know for sure for a while, as it's possible any changes may take a while to propogate, just a heads up if anyone else has the same problem.