does quantas airlines share frequent flyer miles with any u s domestic airlines?

Answer 1

Qantas Airways is a member of the oneworld airline alliance. The only US airline in that alliance is American Airlines, so you can use those miles.
You can also earn or use miles with Qantas' partner airlines (US airlines listed only):
Alaska Airlines
US Airways (Please note that they US Airways will cease to be a partner airline on February 28, 2007.)

Answer 2

(Adding to the precious answer) You can also fly Qantas and opt to earn Continental miles.