Best way to find a version in snapshots depending on existing install

[David Goodenough <david.goodenough@btconnect.com>]

I have a machine which is running a fairly old version of Debian, onto which I
wish to add a new package.  I have tried various versions of this package but
they all want later versions of things like libc6 than are installed.  

Upgrading the machine just for this package is not currently an option so I 
want to try to do it using the existing packages.

I could simple download each version in turn from snapshots and try it, but 
that might be time consuming.  Is there a way of forming a question to 
snapshots which would tell me which to install?  Alternatively is there an
easy way to list the dependencies of each version on snapshots of a particular
package?

David