A federal judge ruled today that a gender discrimination lawsuit against Wal-Mart Stores can be expanded to a class-action with 1.6 million plaintiffs. US District Judge Martin Jenkins in San Francisco granted class-action status today after months of hearings. Wal-Mart spokeswoman Mona Williams says the Bentonville-based retail giant will appeal, but doesn`t believe Jenkins` decision had anything to do with the merits of Wal-Mart`s case. The lawsuit was originally brought by six women who alleged Wal-Mart promotes and pays men more than women. At its shareholders meeting earlier this month, Wal-Mart promised to promote the same percentage of women as the ratio of women who apply.