Presumably it is against the Ts&Cs of the hosting service itself as they are region locked for a reason - otherwise why would they both to region lock in the first place?
The rights to the football will have included restrictions on region. This is implemented by those who are then providing the service and presumably they have to show somehow that they are implementing those blocks. If they get lots of people bypassing the blocks then presumably they may have their license to use the content revoked.
Whether you are liable under UK law is something I can't answer but I would be fairly sure you are in breach of the terms of the service you are accessing. Although, looking at Al Jazeera's Ts&Cs they are governed under English law and use English law courts despite England not being a country that they advertise as providing service to.
Edited by ian72 (Fri 13-Sep-13 14:20:39)