I agree. But I'm also thinking that you (me, anyone) wouldn't know what the company are up to with this. Seems like a strange reason to ask someone to
forgo their raise so that another may get his.
Rather than give a flat out no, perhaps better to use: "Currently I have gone over my household budget with the mrs for the current year and as is, we are just about staying in the black. Hopefully by 2010, should you be making the same request, I will be in a better position financially to acquiesce to your request."
Or words to that effect. Plus, if they are thinking of firings down the line, reminding them that you're practically on the breadline already might make them think twice about firing you.