Question: 2-D output problem

I have the following problem in normal 2-D output: Greek letters appear not to show up.
Here is an example of the issue (screen shot):

The lprint shows that the name in fact is there.The problem does not show with character-based output but is independent of just about any other setting (like standard or extended typesetting).

I am using Maple 15 on OS X 10.4.11 (Tiger) on PPC. Adding to the weirdness is that it shows up on one of my systems but no on another one even though both are configured in a very similar manner (same system, same Maple). Font sets should be very similar on both machines, and on the one exhibiting the problem I certainly have Greek characters in various fonts. I am not aware of corrupted fonts on either of my systems, although it isn't clear how I would know. I checked the logs but have not found anything related in there.

I have seen this for a while but now it really inhibits my work.

Maybe someone knows which fonts are actually used?

TIA,

Mac Dude