Xerox Corp., said fourth-quarter profit could be as much as 40% below analysts' estimates, crippled by expenses for its sales-force reorganization, Y2K concerns and competition. Stamford, Conn.-based Xerox was expected to earn 66 cents a share in the quarter, the average estimate from analysts polled by First Call Corp. Chief Executive Richard Thoman said concerns over possible Y2K problems were keeping customers from buying Xerox's profitable printing and publishing equipment for their computer networks. Profit is also being hurt by the appreciation of the dollar against major European currencies and by lower-than-expected results from operations in Brazil, Xerox said. "While I am disappointed with these adverse developments, the primary reasons are clearly unrelated to long-term fundamentals," Thoman said in a statement. "Our earnings will show meaningful growth in the second half of next year." Xerox shares fell $3.56 to $19.88 in late trading on the New York Stock Exchange.