I also had mixed experiences with the power outlet in the 330s. I was using an earlier model notebook, Compaq Evo and could not get enough juice form the socket to just power up. It happened in both classes. But now, I switched to an IBM T42, it worked fine.... even charged the battary. The only think is that I am using a British standard plug and I have to use an adaptor. At times I have to tweat it a little bit to get it started, but once it works, it works.....
Good luck with it.