Its Asian supplier is said to be opening 50 new productions lines to meet demand

    DigiTimes, the Taipei-based daily that covers the Far Eastern electronics markets like the Sporting News covers baseball, reported Tuesday that Apple (AAPL) has stepped up production of the iPad in China.

    The item is unsourced and like all supply-chain reporting should be treated as a rumor. But according to unnamed "sources from upstream component makers" Foxconn has started mass-producing iPads at a new plant in Chengdu, China.

    Currently, Foxconn assembles most of Apple's iPads in its giant Shenzhen facility. The production lines there are said to be capable of building up to 2.5 million iPads per month, with volumes that fluctuate based on component supplies.

    Currently the new plant can only turn out a maximum 10,000 units per day, according to DigiTimes, but its sources say Foxconn has plans to set up about 50 iPad production lines in Chengdu with an annual maximum capacity of 40 million units.

    Despite supply constraints, Apple sold 7.46 million iPads in the device's first six months. Most analysts expect the company to sell between 5.5 million and 7 million iPads in the quarter that ends Christmas day.