Socialism with Chinese characteristics means the celebrations are a dizzying combination of cold-war icons and contemporary capitalist chic. Despite the hammer-and-sickle branded jollity, the communist hierarchy is keenly aware of the challenges facing the party and President Hu Jintao renewed his call for comrades to combat spreading corruption, which he said was sapping the government's authority.

Great Chinese icons and achievements, such as the skyscrapers of Shanghai; the world's biggest dam at the Three Gorges, the Tibet railway, which is due to start running today, as well as the space capsule Shenzhou 6, have featured in the television advertisements for the birthday events, all emblazoned with red stars, hammers and sickles.

The communist party is flourishing, with nearly 71 million paid-up members last year. The party has proven more ideologically flexible than Karl Marx ever would have suspected. The organisation that celebrates its birthday today is a very different kind of communist party from the one founded by a gathering of some 50 radical intellectuals in Shanghai in 1921. For one thing, the Marxist-Leninist party has taken capitalism to its bosom, though democracy is still not an option.

"The communist party always attaches great importance to maintaining and developing the progressive nature as a Marxist party, " Hu said in a speech. Reinforcing ideological loyalty and spreading wealth to China's poor could ensure that the party remains in power even as it deepens market reforms, he said. "We must grasp the lengthiness, complexity and difficulty of fighting corruption and promoting clean government. If a ruling party cannot maintain flesh-and-blood ties with the people; if it loses the people's support, it will lose its vitality, " he said.

This week, China sacked the deputy head of the navy, Wang Shouye, for "economic crimes" and "loose morals" after he was denounced by his mistress. A deputy governor in the eastern province of Anhui was detained for taking bribes, and earlier this month, the Beijing deputy mayor, Liu Zhihua, responsible for allocating some Olympics projects ahead of the Beijing Games in 2008, was sacked, accused of corruption and dissolute behaviour.

In recent months, Hu has overseen a reeducation campaign to instill discipline, Confucian-style ethics and ideological loyalty among the rank and file.