Shares in mobile-phone firm Sunday Communications fell five per cent on their Hong Kong trading debut yesterday, despite having risen 41 per cent in the US overnight. The company, which has a dual listing on Nasdaq and the Hong Kong Stock Exchange's main board, was hit by a further sharp slide in technology stocks and the Hang Seng Index. The index fell 388.2 points, or 2.31 per cent, to 16,359, partly on concerns about Premier Zhu Rongji's hardline warning on Wednesday to Taiwanese voters over tomorrow's presidential election. The index has lost 1,472 points, or more than eight per cent, this week. Many technology-related stocks posted heavy falls following warnings by regulators of the risks of investing in the sector. Pacific Century CyberWorks lost 3.1 per cent to $19.95, Tom.com dropped 8.71 per cent to $11 and Hongkong.com fell 18.51 per cent to $3.30. Sunday opened yesterday at $4.50, 22 per cent above its issue price of $3.78, but fell back to finish the day at $3.57. The share offer was 35 times oversubscribed. The stock was the day's second-most actively traded, with 242 million shares worth $940 million changing hands. Brokers said Sunday's debut did not augur well for Sunevision Holdings, whose shares begin trading on the Growth Enterprise Market today.