UPDATE 1-Alibaba.com says report of IPO for unit old rumour

(Writes through, adds company comment, changes dateline)

BEIJING/NEW YORK, April 30 (Reuters) - Alibaba.com Corp., which is partly owned by Yahoo Inc. (YHOO.O), said on Monday reports it was planning an initial public offering in New York or Hong Kong for one of its units was an old rumour.

"This is a new version of a rumour that has circulated for the last couple of years," Christina Spindler, a spokeswoman for the Internet company told Reuters.

The Chinese firm plans to list its business-to-business operation and does not plan to make its other units part of the IPO, the Wall Street Journal reported on its Web site on Monday, citing an unnamed source.

Late last year, Jack Ma, Alibaba's founder and chairman, told Reuters that he had frozen plans to go public because he wanted to focus on building the business rather than on financials.

In November, Alibaba.com hired an M&A veteran and former president of B&Q China, David Wei as president the firm's business-to-business division.

Wei was previously managing director and head of investment banking at Orient Securities Company Ltd., and has also worked at Coopers & Lybrand, now PricewaterhouseCoopers. (Additional reporting by Paritosh Bansal)