The latest must-have items - cotton aprons, tote bags and pouches - come emblazoned with the character for 'jail' inside a circle and are cut, sewn and assembled by inmates at Hakodate Juvenile Prison on the northern island of Hokkaido.

The items first went on sale in October 2006 as souvenirs for tourists and prison visitors, but did not catch on immediately.

The line's popularity picked up suddenly last year when a government-backed corrections association began to carry the logo at its Tokyo outlet store, said Mr Shoji Nakajima, an official at the Correctional Association for Prison Industry Cooperation.

With orders flooding in on the association's Internet shopping site, all items are currently sold out.

The demand has been so great that it is planning to register the logo - designed by a prison official - with the patent office, Mr Nakajima said.

'We thought the character for 'jail' would turn people off but that turned out to be the big appeal,' Mr Nakajima said. 'Young people seem to like it especially.'

The association also sells hundreds of other items ranging from furniture and portable shrines to tea cups and green tea, produced by more than 81,000 inmates at 70 Japanese prisons as part of compulsory prison labour.

Many inmates are assigned to unskilled labour such as assembling shopping bags and envelopes, but Mr Nakajima said he hoped Hakodate's success can be a good lesson for other prisons to become more creative.

Under Japan's criminal law, the production lines are part of corrections and vocational training and not for profit, Mr Nakajima said.

The Hakodate inmates do not get any bonus from the booming sales of the jail brand and any profit will be used to fund the labour programme, he added.

'Inmates are not allowed to work overtime,' Mr Nakajima said. 'And the prison cannot hire additional staff.'

Aprons with the striking logo - which sell for about 1,260 yen (S$16) each - have grabbed the attention of fans at a bar in Tokyo's bustling entertainment district of Shinjuku, where a manager and two waitresses wear them regularly.

Figures were not available for all products, but 5,300 copies of the best-selling apron have been sold.

'Our customers have said the design is cool despite what the logo means. They often ask where they can find them,' said bar manager Mariko Yoshida, 52.

'They're of good quality too.'

ASSOCIATED PRESS