I'm using the Diecimilia w/ ATMEGA168 bootloader that is listed in the Arduino IDE, as recommended by the the breadboard tutorial.
I've tried sending a manual reset using my push button, but the effect is similar to NOT pushing it; at best, my Arduino LED just flickers for a couple seconds. In either case, while this is happening, I also see the Receive lights flash on my USB-to-serial breakout. Then the Transmit light flashes slowly, before it gives up and I get the avrdude synch error.
Are there any special COM port settings perhaps that I should be aware of?