PictureTel Corp, the Andover, Massachusetts-based videoconferencing equipment vendor has warned that revenue for the fourth quarter ended December 31 will fall short of analysts’ expectations. The company now expects revenue of $98m for the quarter, down about 4% from the preceding quarter, when Wall Street was looking for a 3%-7% increase. As a result, PictureTel said it expects to report an operating loss of as much as $6.0m for the quarter before one-time acquisition charges. The shortfall is being blamed on a delay in shipping its new SwiftSite II compact videoconferencing system, which was set to go out in the fourth quarter, but will now ship sometime in the current one.