Yes, it will run on a 3400c. There is no sleep support or battery monitoring, and PC card support is limited to CardBus (no 16-bit cards, it would seem). I think I read that the backlight control is non-functional and that the backlight is on full, as well.

144 MB RAM is probably helpful.

I just installed it on my 2400c/240 via XPostFacto on a 9500 is SCSI Disk Mode, but I can't boot it. I'm not done playing around, yet, though.

Peace,

Drew