Immigration minister Phil Woolas recently admitted that the student visa system is "the major loophole in Britain's border controls".

CENTERFORSECURITYPOLICY: Center For Security Policy

Is there a loophole in the immigration system?

WHITEHOUSE: Press Briefing

Then there are the boats based in Northern Ireland, often staffed with diligent, sober Filipinos taking advantage of a loophole in the visa system, who cope with the privations of life at sea better than the average Scot.

ECONOMIST: Fishing in Scotland