So I bought a (new) 1st gen holder off ebay from a hong kong store and my iphone doesn't fit too well in it. In fact, I have to push kinda hard to get the phone to make contact, much harder than it should be. I don't have the bumper case, this is just the bare iphone. Also, the square mark on the holder is above where you plug the cord in, but you have to plug it in upside down because that's the way the connector is mounted.
I opened it up and it's different from the pics someone posted here. Obviously some chinese knock-off of the real deal, so buyer beware.
I suppose I'll have to break out my dremel to make it fit in easily, or just use it without the plastic mounting. It's basically just a ciruit board with a connector at each end and an audio jack to one side.
Eh, but what can you expect for $6.99?
Followup: Just tried to use the Line Out audio jack. It doesn't work either. *sigh*