Just ask Yoshiaki Murakami, who may be the closest thing Japan has to the character Michael Douglas made famous in 1987. The 46year-old Murakami isn't known for ruthlessness, but is a brash activist pushing for shareholder rights, arguing that they will boost the economy. "The reason I'm disliked is because I made a lot of money, " Murakami said on 5 June, sounding a bit like Gekko.

Murakami's chances of shaking up Japan Inc's clubby world are slim now that he has been arrested for insider trading. It's the second time in four months that a maverick has ran foul of regulators, the other being Takafumi Horie of internet start-up Livedoor, suspected of violating securities laws.

So far, investors aren't impressed with the Murakami situation, but it's unclear whether they should be disillusioned because Japan's best-known financial activists may be crooks or wondering whether corporate Japan is closing ranks to silence trouble makers.

While the first question can't be answered authoritatively yet, the second is worth exploring. In his five years plus as prime minister, Junichiro Koizumi has argued for market solutions to Japan's challenges, a major change in tone for what is essentially a one-party state, but the country's muchheralded 'Big Bang' in the 1990s seemed more of a damp squib. And as soon as a few larger than life capitalists stepped up to take advantage of liberalisation, regulators whacked them.

Many investors looking at Japan's most convincing recovery in 15 years are confused by the weak stock market. Here you have the world's No 2 economy returning from a neardeath experience and growing faster than 3% a year, and the Nikkei index is still down 4.5% so far this year.

The Nikkei's performance is about more than Murakami or dodgy corporate dealings, though. Apart from global concerns . . . oil prices, the threat of a US dollar plunge . . . it is also rooted in the realisation that Japan is growing complacent. The ruling Liberal Democratic Party has a long record of acting decisively during crises and then shelving reforms when the good times return . . . like now.

Deflation hasn't been eradicated as quickly as many economists expected, nor have households spent their vast savings with the abandon many politicians anticipated. Perhaps investors also realised that the heavy lifting begins now that Japan is growing again.

For all the acclaim Koizumi has won for modernising the economy, the government is not working to reduce a debt-to-GDP ratio that's near 151%. Nor is Japan dealing with its demographic problems. With an ageing population and a low birth rate, the number of Japanese actually shrank in 2005.

There has been considerable change: the banking system is stable, corporate balance sheets are healthier, tax policies are being tweaked to boost entrepreneurship, the postal savings system (home to trillions of dollars that politicians use to fund pet projects) is being privatised and the Bank of Japan is poised to end its zero interest-rate policy.

Yet, little attention has been given to bringing Japan to the next level. Long ambivalent about foreign investment, the country still isn't doing enough to attract it. That will be even harder if foreigners worry that regulators will pounce if they demand Japanese companies become more shareholder friendly.

Since World War II, Japan has rarely been serious about insider trading. That is now changing, which is a move in the right direction. But when redoubling efforts to punish securities laws violators, it would help if the two main targets were not outspoken critics of Japan Inc.