When querying a package, rpm tries to open a database. However there is IMHO no need to have working database when querying file on disk. And rpm also gives the response, just also prints some errors.
$ rpm -qp --queryformat '%{VERSION}\n' ~/archivemail-0.6.1-3.ae.src.rpm
error: cannot open Packages index using db3 - No such file or directory (2)
error: cannot open Packages database in /var/lib/rpm
warning: /home/joey/archivemail-0.6.1-3.ae.src.rpm: Header V3 DSA signature: NOKEY, key ID 4e6c9f5e
0.6.1
(Forwarded from Debian BTS - http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=451441)