Car charger not working

Hi all,
I got bought several car chargers that claimed to be for the G1. They plug in fine and I thought it worked with my phone, but today it wasn't working at all as far as I can tell. Both my wife and I have G1 phones and it definitely worked with her phone on Sunday, charged up in a couple hours drive that we had. Today, mine wouldn't charge at all. Was about 1/2 charge or a little less, but went all the way til the battery level gauge turned orange.

Could there be something odd with my phone or is the charger just sucky? Is there some setting. A friend told me some manufacturers are putting chips in the chargers to make them only work with their phones, or more precisely the phone will only work with their charger. This kind of defeats the purpose of having a universal charger for all phones, but I don't put it past them if it is true. Bastards!

Any ideas?