I'll note that, at least in business, some research indicates that women do not earn less than men: "Women executives who do not have children follow career paths that closely replicate those of their male peers. Successful M.B.A. couples have similar work patterns, said Dr. Bertrand. Women without children married to high-earning spouses are just as likely to work and accumulate post-M.B.A. work experience at an almost identical rate, she said. Call a woman without a child a man."

Rather, they work less than men: "When women executives return to the office, after several months of absence, they typically start to work shorter hours, the study shows: 52 hours per week, compared with an average 58 hours for their male peers, as they adapt to their new double task."

http://www.nytimes.com/2009/04/29/business/global/29iht-ried...

This is not brushing away the problem, but pointing out that wages are a symptom of an underlying cause.