Nasdaq Stock Market said today that it has pushed back the onset of...

Nasdaq Stock Market said today that it has pushed back the onset of extended trading hours to Oct. 25. The electronic quotation market had planned to go to extended hours Oct. 1. "The delay responds to concerns from some broker/dealers that they need time to modify their internal systems that process and generate trade reports after 4 p.m.,’’ said J. Patrick Campbell, Nasdaq’s chief operating officer. "The postponement will provide them an opportunity to make adjustments to their systems or modify their processes,’’ said Mr. Campbell.