SHANGHAI -- Tokyo developer Mori Building Co. has revised a controversial design for a skyscraper planned for this eastern Chinese city.

First proposed in the mid-1990s, the Shanghai World Financial Center was to be topped by a giant circular opening that the architects said would stabilize the structure on windy days. But for Shanghainese, the design symbolized the rising sun of Japan's national flag and evoked memories of the Japanese Imperial Army's brutal 1937 occupation of the city.

Moving forward now is an even-taller, 472-meter building with a trapezoid-shaped opening featuring a 100th-floor observation platform at its top and exhibition spaces. "We felt this was fresher" than the circle, plus cheaper and more efficient, said Minoru Mori, president and chief executive of the development company.

The saga of the Mori building has followed the ups and downs of Shanghai's dynamic property market, and in particular the city's Pudong financial district. Mori's decision to dust off and revise the ambitious building -- which is set to be one of the world's tallest when it is finished -- is testament to the property boom sweeping Shanghai and the rest of China, despite government efforts over the past few years to cool what some believe is an overheated sector.

The Mori building was proposed for the Pudong district during the city government's push to transform what was then a depressed area of factories and farms into a virtual new city of modern architecture and high-rise office buildings across the river from the heart of Shanghai. But Mori never got much further than the groundbreaking in 1998, before the "rising sun" controversy and signs of an overbuilt office market prompted him to freeze the project.

Furious building in Pudong means the area now appears poised to become Shanghai's main office market. It had an office vacancy rate of just 7.4 percent in July, compared with a 1997 peak of 67 percent, said Michael Hart, head of North China property research at Jones Lang LaSalle in Shanghai.

Mori said that as long as China's financial liberalization continues, "space will become sparse" again when his landmark opens in early 2008. A key tenant will be the Hyatt hotel chain, which plans to open a Park Hyatt, the company's most luxurious nameplate. That hotel will join an increasingly crowded market. Across the street, the Grand Hyatt Shanghai has been operating a 555-room hotel since 1999. Two blocks away, the Shangri-La hotel chain last month expanded its seven-year-old, five-star hotel, the Pudong Shangri-La, to nearly 1,000 rooms by opening a 36-floor annex.

Kohn Pedersen Fox Associates, the architecture firm hired by Mori to design the building, said the huge aperture at the building's top was not intended to symbolize Japan.

Mori Building Co. chief executive Minoru Mori, right, and A. Eugene Kohn, chairman of architectural firm Kohn Pedersen Fox Associates, stand near a scale model of the revised Shanghai World Financial Center.