Fonts in EPS Files

[Jeff Aigner <jaigner setnine com>]

I am trying to create a library that outputs to EPS files and running
into an odd issue. When I output to PNG, text seems to appear fine (all
the various fonts work). However, when I output to PS, EPS, or PDF, I
get errors like the following from pretty much any Adobe based product:

f-0-0-Identity-H:
	Font not found on system; missing font has been substituted.

If the font being used is a TTF, the (Adobe) program will substitute the
proper font (after the annoying message). If it is an OTF, all of the
individual glyphs become rectangles with X's through them. I have the
font installed on both the system generating the file, and the system
opening the file.

I've seen EPS output claiming to be generated from Cairo that actually
has text contained without these errors, yet I cannot figure out how
they embedded or converted the fonts to paths.

Any help would be greatly appreciated,

Jeff Aigner