ssl with pem password

hi.....I'm trying to use postgresql in mode ssl and I would to use a
private key that uses a pem password.  When I launch postgres with
postgres user and my server.key and server.crt in my home ,in this mode:

echo password | /usr/bin/postmaster -il -p '5432' -D '/home/data'

I see this message:

Enter PEM pass phrase


but I would a thing more automatic without that password request. Is it
possible?