[WEBDEV - PHP] Problem with font when drawing on image

I can draw the text on an image before I display it, but I don't seam to be able to change the font type or size.

Here's the code that generates the text:

dStartDrawing(IMG_Seal)
IMG_Seal = "test.jpg"
dFont("Arial", 12, iBold)
dText(30,130,sCode,White, False)

Any ideas why dFont doesn't do anything on the PHP site?

Thanks

Jonathan