backportpackage set default gpg key

[eyelessfade]

When I try to backport a package with

backportpackage -s oneiric -d lucid package -u ppa:myppa/ppa

It fails with: <username@computer>: secret key not available

How can I specify which gpg key to use. I've already tried with export GPGKEY

[MadCow108]

put DEBSIGN_KEYID=keyid in ~/.devscripts

[eyelessfade]

put DEBSIGN_KEYID=keyid in ~/.devscripts

Thanks that worked great.