Default BitmapFont support black-white image only?

hnim

i convert bitmapfont data to use with default gideros font, but it display grayscale image only. is it normal?
i use this code to make font:

local font = Font.new("font.txt", "font.png", true) local text = TextField.new(font, "the quick brown fox jump over the lazy dog")

and here's result. first line i use BMFont lib, default font in second line.