* All 28 stocks double from IPO prices in intraday trading
* Film maker Geeya, Huayi outperform on celebrity appeal
* Frequent trading halts point to heavy speculation
* Huge interest creates billionaires, good for upcoming IPOs
* Large number of firms in pipeline to go public on ChiNext (Adds details on listings in paras 6-7; share price details in paras 7, 10-12; updates prices/values)
By Lu Jianxin and Edmund Klamann
SHANGHAI, Oct 30 (Reuters) - The ChiNext stock market, China's long-awaited Nasdaq-style second board, debuted on Friday with a speculative surge that more than doubled the price of all 28 stocks during intraday trade -- a good sign for companies lining up to list on China's stock markets.
The bubbly open to a market that hopes to turn local start-up firms into budding Microsofts or Intels stirred concerns about speculative froth, but analysts said circuit-breakers would curb excesses while a steady supply of new shares would help to keep mainland stock valuations under control.
"We certainly won't build positions at such high prices," said a senior manager at a Chinese mutual fund, who could not be quoted by name as he was not authorised to talk to the media.
The huge interest has created dozens of yuan billionaires overnight among the firms' founding shareholders, while retail investors lucky enough to win an IPO subscription lottery could cash in on the debut day for up to 40,000 yuan ($6,000) -- a small fortune for China's small investors.
ChiNext, part of the Shenzhen Stock Exchange in booming southern China, started out with a market capitalisation more than 100 times that of China's main Shanghai Stock Exchange, which launched in 1990, and vastly deepens China's capital markets by expanding funding channels for small innovative firms.
Regulators are reviewing more than 100 IPO applications for ChiNext and industry officials estimate that at least 1,000 firms are preparing to float shares on the market next year.
China has 10 million small and mid-sized companies starved for loans from domestic banks, which favour big state-owned enterprises. Spurred in part by a lack of immediate access to funds at home, 22 Chinese start-ups have joined the U.S. Nasdaq Stock Market this year, bringing the total of such firms listed on the U.S. market to 116.
BILLIONAIRES
Market players had expected at least one-third of the ChiNext stocks to more than double on the first day, and while all 28 achieved that goal at some point during the session, only 36 percent managed to retain those gains to the close.
It is typical for IPOs listing in Shenzhen to double or triple on their debut because of their low capitalisation.
ChiNext also halted trade in all the new stocks at least once for 30 minutes during the morning after they rose 20 percent from their opening price, triggering exchange circuit-breakers intended to curb excessive speculation.
Most were hit with a second 30-minute halt when they extended their gains to 50 percent, and a handful, including film studio Chengdu Geeya Technology Co, were hit with a third halt after shooting up 80 percent.
Geeya was the biggest gainer of the day, more than tripling from its IPO price, while rival Huayi Brothers Media Corp was the most actively traded stock, with investors drawn by the famous celebrities associated with the two firms.
The value of Huayi Chairman Wang Zhongjun's shares in the firm ballooned to 3.1 billion yuan, while Pu Zhongjie, president of medical equipment maker Lepu Medical Technology, saw his holdings' worth surge to 3.8 billion yuan.
"Almost all companies have now seen their share prices surging to excessive valuations, betraying rampant speculation," said Zheng Weigang, head of investment at Shanghai Securities.
"Such intense investor enthusiasm bodes very well for upcoming IPOs on the market, but we expect speculation to die down after a couple of months or so, mainly because regulators are pushing large numbers of new shares into the market."
INVESTOR ENTHUSIASM
The 28 listees, almost all private companies in contrast with the state-owned corporations that dominate China's main board, completed recent IPOs at prices averaging 56 times 2008 earnings.
Based on forecast 2009 earnings, analysts estimated the average price/earnings (PE) ratio for the IPO prices at around 40 times, while the huge gains in Friday's trade pushed that up to around 75 times, according to Reuters calculations.
Investors have not been deterred by the high prices, however.
The companies raised a combined 15.5 billion yuan from their IPOs, with an average oversubscription ratio exceeding 120 times.
The high valuations on ChiNext appeared also to boost China's main board, where the benchmark Shanghai Composite Index closed up 1.2 percent. The average forecast PE for main-board shares is about 30 times.
ChiNext's initial 28 start-ups had a market capitalisation of 70 billion yuan before trading started, doubling to about 140 billion yuan at the close.
In contrast, the Shanghai bourse listed only eight firms on its debut in December 1990, with a combined market capitalisation of less than 700 million yuan. The exchange, now boasting a capitalisation of 17 trillion yuan and the world's fifth largest, traded only 126,000 shares worth 494,000 yuan on its first day. (Editing by Ian Geoghegan) ($1=6.83 Yuan)