aptitude update gpgv error

[Lubos Vrbka <lubos.vrbka@gmail.com>]

hi guys,

i can see the following error when doing aptitude update on my freshly 
installed etch i386 system:

W: GPG error: http://security.debian.org etch/updates Release: Unknown 
error executing gpgv
W: You may want to run apt-get update to correct these problems

when i try to execute gpgv i get the following error

# gpgv -v
gpgv: can't allocate lock for `/root/.gnupg/trustedkeys.gpg'
gpgv: keyblock resource `/root/.gnupg/trustedkeys.gpg': general error

indeed, trustedkeys.gpg is not present. when i create it by touch 
trustedkeys.gpg, this error disappears, but the error from aptitude 
persists.

any hints? thanks,
lubos