Reasons an output pin wouldn't go high?

I'm using a SparkFun-built Arduino Pro Mini 3.3V / 8MHz. One thing I need it to do is toggle the gate pin on a MOSFET, and that's not working for some reason. Getting in there with a multimeter, I see that the voltage on the pin never goes HIGH. The only thing I have running on there is the following bit of code:

void setup()  {
  pinMode(A7, OUTPUT);
}

void loop() {
  digitalWrite(A7, HIGH);
}

Any thoughts on either configuration or electronics that could be causing this?

From a wiring standpoint, the only thing I have between that line and the MOSFET gate is a 100R resistor.

The extra analog pins (A6, A7) do not work as digital output pins (the standard ones A0 .. A5 do).

Crap. So there's no way to make them go high? They aren't PWM pins either?

So there's no way to make them go high? They aren't PWM pins either?

They aren't nuthin' but analogue inputs.


Rob