Workers at Cisco hoping to make shedloads in Christmas overtime can forget it.

For the first time in ten years, in a bid to save money Cisco Systems will close most of its U.S. and Canadian offices for 4 days over the holidays. The move is part of a plan to cut $1 billion in costs in the current fiscal year, the company said.

Demand for Cisco's computer networking equipment remains sluggish, forcing the company's first mandatory shutdown in over a decade. The outfit said that sales will fall 5 percent to 10 percent in the current quarter as the credit crisis strangles spending by corporations.

Cisco wouldn't say how many employees will be affected by the closure or how much money it will save because of the decision. Most Silicon Valley companies shut down over the holidays when business is slow and employees are on vacation. However, some are now extending those closures, or revisiting a practice long since eliminated in a bid to save money in a rocky economy.