That's a very interesting link Sunny.
It seems to be a very unusual scheme - defined benefit but with defined contributions... So people retire on defined benefits and if their lifetime contributions (including the employers' contributions) aren't enough, they get topped up by current contributions (which should be accruing for current employees). In hindsight, you can see that it's a pretty poor deal for newer and newer employees - almost like a ponzi scheme. It was fine as long as life expectancy was low, investment returns were high and there was an increasing workforce. What a mess. On the face of it, it looks like the ESB is contractually correct - if the scheme never obligated them to pay more than their agreed contribution level, how can the employees demand that now? It would be very interesting to see the wording of the employees' contracts.