grap problem

[Chuck E. Rudolph]

I am having a problem with troff's grap utility.

I have 2 grap variables that I need to pass to a shell command except that I
can not seem to dereference them.  The following grap script illustrates what
I am trying to do.  To run it, but the next 5 lines in test.grp and issue
'grap test.grp >/dev/null'.

.G1
start_date = 19901112
end_date = 19910102
sh X echo 1>&2 start_date end_date X
.G2

What I want to see as output is:
19901112 19910102

What I am currently getting is:
start_date end_date

----------------------------------------------------------------------
Chuck Rudolph                     Electronic: uunet!motcid!rudolph
Motorola Inc, N349                     Voice: (708) 632-2779
1501 West Shure Drive                    Fax: (708) 632-5694
Arlington Heights, IL  60004      Disclaimer: It's mine... All mine...