I have read a couple of interesting posts recently about the wussitude of AD&D dragons (see Beedo's post here and Peter D's post here). I can remember my gaming group coming to the same conclusion back in 1977 as we were reading through our brand new copies the Monster Manual. It seems like the game's namesake--a monster that should have been at the top of the food chain--was a bit of a powderpuff (this assumes that one avoided the breath).
Our solution, at the time, was to revamp the hit points of the dragons in the following way: Instead of dragon hit points being based solely on age (X hit points per die, where X is the growth stage of the dragon), we counted original system as additional hit points added to the hit points that we rolled.
Consider the following table, which uses a red dragon of average size (10 hit dice). The column on the left shows the hit points for each dragon age, using the dragon hit point system on page 29 of the Monster Manual (AD&D 1e).