decrypt failure using scheduling tool on UNIX; receive msg 'cannot open /dev/tty'

[Kaipust, Michael]

All,
The following command executed in a Korn shell script from our scheduling tool is yielding the message:
gpg: cannot open /dev/tty: No such device or address

command-
gpg --recipient "Qwest HRBATCH"  --passphrase-fd 3 --output output.txt --decrypt in.txt.pgp   3<pswd.txt

I had hoped that I could get around problem by utilizing a file-descriptor (fd) other than 0 (std input) but the stmt above still results in the /dev/tty error