RPM meta package

I have a package which previously depended on postgresql92-odbc, but I
would like to be able to upgrade that without explicitly changing the
dependency, for all future versions. Maybe something like "depends:
postgresql-odbc > 9".

The various postgresql-libs RPMs provide this - i.e., I can install
postgresql94-libs and it satisfies any dependency for postgresql-libs.
But the only RPM that satisfies the dependency for postgresql-odbc is an
old one:

> yum provides postgresql-odbc
postgresql-odbc-08.04.0200-1.el6.x86_64 : PostgreSQL ODBC driver
Repo : base

Is there some reason that postgresqlxx-odbc RPMs don't provide the
virtual package for postgresql-odbc, so that whatever version I have
installed will fulfill the dependency?

Thanks,
Jeremiah