I have a luminosity-based SMask being applied to a colored rectangle.  This 
SMask contains partially-opaque letters on a transparent background.

For a given pixel, the opacity applied to the rectangle is only one of two 
values -- either 1) the opacity of the overlapping letter or 2) fully 
transparent.  There is no antialiasing of text in the SMask, even with 
dTextAlphaBits/dGraphicsAlphaBits=4.  This results in jaggy letters.  Acrobat 
Reader antialiases the transparency mask.

Consequently, my application has to render at 4x and resample, which takes a 
long time.

Minimalist PDF located at: AntiAliasingColorCheck.pdf