The recent upgrade of our mail server last evening has knocked the internal instant messaging service offline for webmail users. External (third party) instant messaging services may be impacted if you are using the secure port (5223).
The internal instant messaging provider will be releasing an update within a few days which will bring things back to normal.
In the meantime there is a work-around if you are using a third-party instant messaging system: use port 5222.
We apologize for the inconvenience. It was not an easy decision to make (taking the chance of losing IM services) but in our opinion addressing major the security issues outweighed maintaining webmail-based instant messaging.
Keep an eye out on our Twitter account and watch this blog for updates.