I have to admit that I have a blind spot about this situation, but maybe you know someone struggling with the problem in this FundAlarm.com post:
Working past "retirement": RMDs & taxes
"It is churlish to complain, because I am lucky to have the job I have -- and love -- & thus be in this ironic position....but
For the second year in a row my RMDs will push me into the AMT. (Remember how those tax-sheltered savings would surely be taxed at a lower rate in your "retirement"??)
If more people work longer -- as we are told to expect -- lots more folks may land in this position of taking RMDs while still employed.
I have no intention of trying to do the math, but I sometimes wonder if I would have been better off to just invest & forget tax sheltering. Another case where one can never predict the future -- or the tax code."
So... I guess that's one way to end up in a higher tax bracket when you're subject to RMDs!