A second referendum on the same question is somewhat pathetic, yes. But then, so is the absurd misinformation spread by opponents of Lisbon, and the fact that European elections in most countries have more to do with voting for or against the current government than with Europe. Of course to some extent that's the EU itself failing to get much enthusiasm from Europeans, but to some extent it's also the national governments that are to blame.
And the reason why all the pressure was brought to bear on Ireland is precisely that the EU has grown too big for unanimous decisions, and that reforms are needed to allow non-unanimous decisions - but those reforms have to be accepted first.