This issue was resolved at 17H10 last night. No feedback from upstream provider but it would appear that the networking issue was resolved, and clients are now able to get back into their webmail!
16th April 2015 – there is an issue logging into the webmail interface. We are aware of the problem and our upstream technicians are working on the networking problem. It is 17H19 now and no ETA – please be patient. Thank you for your patience.