No...

OK, let me elaborate a bit more...
With Processing's fonts, .vlw files, you are out of luck, because these are bitmap versions of a chosen system font (and chosen charset). These are handy because they are small and portable, and without copyright problems. But you can't do fancy stuff with that, like scaling arbitrarily or drawing the outline, etc.
Some libraries, like Geomerative, might, perhaps, allow a finer control on native fonts. Keeping in mind that relying on a native font make harder to run your sketch on various platforms.
Actually, one of my first sketches played with fonts the Java AWT way, to workaround the limitations of Processing fonts.
The sketch playing with the Java API is available at http://bazaar.launchpad.net/~philho/+junk/Processing/annotate/head:/Glyph/Glyph.pde
It has lot more than what you need, but you might extract just the stuff needed to draw an outline.

o.k. thanks for the answer. I'll definitely look at Geomerative library and the Java solution.
cheers.

This is a hack but it appears to work:

PFont font;

String message = "Hello";

void setup()
{
  size(400, 300);
  background(0);
  font = loadFont("Arial-Black-48.vlw");
  textFont(font);
  fill(255);
  textAlign(CENTER, CENTER);
  text(message, int(width/2)-1, int(height/2));
  text(message, int(width/2), int(height/2)-1);
  text(message, int(width/2)+1, int(height/2));
  text(message, int(width/2), int(height/2)+1);
  fill(0);
  text(message, int(width/2), int(height/2));
}


You can put it in a subroutine and call it instead of text

void strokeText(String message, int x, int y)
{
  fill(255);
  text(message, x-1, y);
  text(message, x, y-1);
  text(message, x+1, y);
  text(message, x, y+1);
  fill(0);
  text(message, x, y);
}