The underlying question is: should people earn more money just because they’re older? Or should the earn money according to their qualifications? The second options sounds fairer to me, especially if it means that unemployed older people have a fair chance of finding work in the first place.
The Economist just published a special on the problem of the ageing workforce (free for all). The whole article is worth a read, but the following piece of trivia caught me in particular: Britain and Germany used to have more or less the same unemployment rate for people aged 50-65. Not any more, today (2003) the rate is 3.3% for Britain and 9.7% for Germany. And now look at what people earn: In Germany, 50-65-year-old earn 60-70% more on average than 25-30-year-old, but in Britain, it’s roughly the same!