Google Talk for Google domains issue

[Jeff Sadowski]

So yesterday I was connected to google talk when another employee said
she could not connect. I disconnected and could not re-connect with
google talk or with pidgin(Only with Hangouts). Because I was
connected I suspect an authentication change for google domains. Other
people reported that google talk was working fine. I tried with my
regular google account @gmail.com and it works but on my google domain
xyz.com the google account can no longer sign in.