Birthday Woes

My wife is 30 tomorrow and seems to be having some sort of crisis about this fact. She has asked me not to make a big deal of this birthday, as she doesn't want to be in her 30s, it makes her feel old. I've never had such a worry, to me age is just a number, I still think of myself mentally as in my early 20s. The only time my age jolts me is when I fill in some sort of form where the group ages, like 18-25, 26-30 etc. When I move boxes filling in forms is when the reality that I am getting older hits me. I've tried to rationalise things with my wife, we're married, have a mortgage, two children with a third en route so to speak. We can hardly be in denial as to our status. My problem is how to treat her birthday. I've managed to choose presents, buy cards without ages on, but does she really not want to mark her transition into her 30s? Or is this woman speak for don't make a fuss, but I do want a fuss really? I'll perhaps prime eldest born to ascertain the real situation, although given his history of tact that might not be the best plan. I'll sleep on it and guage reaction in the morning perhaps.....