problems open GRADS with crontab

[Isilda da Cunha Menezes]

Hello!
I am with a problem. I want to run a script of shell that opens grads and
runs one gs.script with the instructions  to create the figures, using
crontab. But I am abtain an error message and he does not create the
figures. When I run shell script in the line of commands of consoles does
not have any problem. I find that it is in the parameters of grads that is
the problem. They will be able to help me to correct it error in script of
shell? It has an alternative way to open grads without giving error when
we use crontab?

my script shell is:

#!/bin/bash
DIR=$PWD
gradsc -clb "run gera_figuras-europa.gs" >& grads2.out
if [ $? -ne 0 ] ; then
        exit 8
fi

and the error message:

/home/isilda/simul-BRAMS/RAMSPOST50/figuras/runexp: 3: Syntax error: Bad
fd number

Best regards
 Isilda