I don't think any versions of the bootloader do anything special with pin 6, but I could be wrong; do you see the same behavior on other pins?
It's definitely the pullup being set, the other pins behave the same way when I set the pullups. Also when I reset it with code, the pin goes high at reset then returns low or high Z when the program runs.
These are 168 chips I burned myself. I had to follow some forum links to find the 168 file I think. This was probably ~ 11/06.
At the time my NG came with an Atmega8 so the only 168's I have are the ones I burned. If you wouldn't mind try this out on one of your boards and see if the pullup is set with just a blank sketch.
Is there anything else in the core that might be causing this?
My fuse settings are also slightly variant as recommended in the datasheet for ceramic resonators, I'll burn standard fuse setttings and see if that makes any difference.
I see that there is a 168 bootloader in the playground under uploads, but no link I found (although there probably is one off one of the pages).
Anyway I would think we should get a link up on the bootloader page with the "official" version of the bootloader. It might also be a good idea to include the 168 bootloader in Arduino distributions. I guess the bootloader that comes with the distribution is still Atmega8 because the IDE still won't burn 168's, right?
I'll try the version on the playground to see if it makes any difference.