versions of packages available in other branches

[Kamaraju S Kusumanchi <kamaraju@bluebottle.com>]

Say I am running Etch and my /etc/apt/sources.list contains only entries
related to Stable. Using command line interface, What is the efficient way
to obtain information about versions of a package currently available in
testing, unstable, experimental?

Currently, I go to http://packages.debian.org/packagename to get the
necessary information. But I am looking for a command line alternative.

apt-show-versions -a does not seem to work in this case since all my entries
in sources.list only point only to stable. I do not want to add
testing/unstable entries in sources.list as I would like to track only Etch
and nothing else on this machine.

reportbug seem to be doing this some how. For example if I try to report a
bug in stable's package, it tells me the version numbers available in
testing/unstable. I am looking for something like this.

Any ideas?

thanks
raju

-- 
Kamaraju S Kusumanchi
http://www.people.cornell.edu/pages/kk288/
http://malayamaarutham.blogspot.com/