I'm in the same situation-- just signed my wife up on Saturday.
One of the questions I did a bit of research on was how to state "Total Annual Income" in the application given the situation. From looking around in FT & other forums, the undertone of this question seemed to be focused around "Total Annual [Household] Income". Since my wife is a stay-at-home mom, her personal income is 0, but our overall household income is much greater. We put the total household income in for her app, and it was approved (still stating her as a HomeMaker for occupation).
- John