West Ham had raced into a 2-0 lead thanks to goals from Mark Noble and Dean Ashton but found themselves pegged back before the break when Obafemi Martins capitalised on an error by inexperienced centre-back James
Tomkins to make it 2-1 and then saw a shot go in off team-mate Geremi for a 45th-minute equaliser.
Hammers boss Alan Curbishley said: "We were playing ever so well for 40 minutes and could perhaps be even more in the lead. We just had a crazy couple of minutes.
"It was a terrific ball - the type that Martins feeds on - and Tomkins just got caught under it but that's another learning curve for him.
"That turned the game in their favour. But I'm delighted with the way we played, for the whole game really, but obviously two wasn't enough.
Newcastle manager Kevin Keegan admitted West Ham had been the better side in the first half.
He said: "I would sooner be a lucky manager than a good one to be honest.
"We didn't start well at all and I can give you loads of excuses but what's the point? We weren't at the races.
"They had a good start and we had a bad one, which made it look as though there was a gulf between us in terms of ability, determination and everything.
"But Obafemi Martins can score goals like that. It was a great ball through and a great finish."
West Ham were convinced they should have had a penalty in the second half when the ball hit Michael Owen on his hand.
But Keegan insisted: "If you take the video home look at a couple we should have had in the second half. I'm sure Oba should have had one and maybe Owen as well."