[Groff] Preserve escape characters in output

[cartouchbea]

I have a product I'm trying to port from HP-UX to Linux and I'm hitting a wall 
when trying to use nroff/groff on Linux.  I've tried to RTFM and search the 
mailing list archives for help but so far, nothing I do appears to work.

This product uses nroff to format some files for printing.  Some input files 
will have PCL escape sequences embedded in them that begin with an ASCII 
27/ESC.  Trouble is, no matter what I try, I can't get groff to leave them 
untouched.

Using a file with the following contents:

$ od -c file
0000000   Y   Y   Y 033   Z   Z   Z  \n
0000010


if I run it though nroff on HP-UX, I get the expected output:

$ nroff file | od -c
0000000   Y   Y   Y 033   Z   Z   Z  \n  \n  \n  \n  \n  \n  \n  \n  \n
0000020  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n

*
0000111

but on Linux with groff(nroff) I get:

$ nroff file | od -c
0000000   Y   Y   Y   Z   Z   Z  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n
0000020  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n  \n
*
0000100  \n  \n  \n  \n  \n  \n  \n  \n


Is there anything I can do to get groff to leave that escape character (ASCII 
27/033) in the output?

Thanks for any help

Phillip Anderson