Extruder problem - stepper won't turn

I'm building a repstrap.
I have Motherboard 1.2 and Extruder 2.2
Using firmware from the RepRap 20100308 build download.

When I apply power, all four of the LEDs near the H-bridge light up solid. I measure 6V AC on the stepper connectors. (1A-1 My multimeter says it is 1.95KHz

When a stepper is connected (bare motor, no load) I can hear a faint whine from the stepper, but it does not rotate at all. I also can't get it to respond to "Extrude" from the gui test screen.

My RepStrap... so far

May have found the answer here: Possible solution