Trouble with converting from ps to pdf in OS X

[Nirmal Govind]

Hi.. I'm trying to generate a PDF file from a LyX document that I 
had written under Linux.. I'm now trying to use LyX 1.3.4 under OS X 
 to convert this to PDF. I'm using the tetex and ghostscript 
installations from fink. Looks like the postscript generation goes 
fine but I get an error from ps2pdf when it tries to convert the ps 
file to pdf. I tried running ps2pdf manually from a terminal and 
here's what I get:

> ps2pdf RobustDesignEstimation.ps RobustDesignEstimation.pdf
Error: /undefined in Level27
Operand stack:
Execution stack:
   %interp_exit   .runexec2   --nostringval--   --nostringval-- 
--nostringval--   2   %stopped_push   --nostringval-- 
--nostringval--   --nostringval--   false   1   %stopped_push   1 
3   %oparray_pop   1   3   %oparray_pop   1   3   %oparray_pop   1 
 3   %oparray_pop   .runexec2   --nostringval--   --nostringval-- 
 --nostringval--   2   %stopped_push   --nostringval-- 
--nostringval--   --nostringval--   --nostringval--   --nostringval--
Dictionary stack:
   --dict:1046/1123(ro)(G)--   --dict:1/20(G)-- 
--dict:79/200(L)--   --dict:217/300(L)--   --dict:43/200(L)-- 
--dict:48/68(L)--   --dict:38/60(L)--
Current allocation mode is local
Last OS error: 2
Current file position is 4174327
AFPL Ghostscript 8.00: Unrecoverable error, exit code 1

Any ideas on what the problem might be? This file used to run 
perfectly fine under Linux.. so is this some incompatibility issue 
with the ghostscript under OS X/fink?

Thanks,
nirmal