There is a loss of PPP for some customers this evening.
2010-03-13 21:12: Some customers are unable to login. BT have identified a routing / authentication problem this evening. They are aware of the issue but have not yet identified the cause.
Some more details in this (http://www.idnetters.co.uk/forums/index.php?topic=19269.msg460001#msg460001) post as well