Crikey, two people agreeing with me!
I must be losing my touch.

Me agreeing an' all backpacker. As has been said, if he doesn't sign on when nil work then there's nil NI contributions being credited. He should check out the state of his NI with the local office. Does he keep the Taxman informed of his unemployment?
Someone else mentioned other benefits - depending on his financial status ie savings he could well be entitled to Housing Benefit (if he renting a place) and Council Tax Benefit in other words his rent and Council Tax being paid for him. The Utilities companies also have a system where (again depending on financial circumstances) they give credits to help pay elec/gas/water bills.
Depending on wot sort of work he's done he could probably apply to a charity (s) for help see www.turn2us.org.uk for listings. I'm a Case Worker for SSAFA - Forces Help the ex/current forces national charity and quite often apply to civvy charities (as well as forces benevolent funds) for financial assistance for my clients.