Proper way to specific build-deps on emacsen?

[John Sullivan <john@wjsullivan.net>]

I maintain the planner-el package, which requires some Emacs to be
present in order to build. Previously, specific versions were ORed in
the build-deps field, but that recently failed due to one of them no
longer being in squeeze. My first reaction was to remove all of the
specific versions and just have it build-depend on the emacsen virtual
package, because Planner is meant to be compatible with all of the
current providers of that package. However, lintian warns about this,
saying virtual packages shouldn't be used in Build-Deps. Lucas Nussbaum,
whose automatic tests found the initial FTBFS bug in squeeze, suggested
that ORed build-deps also shouldn't be used because they make the build
non-deterministic.

Any suggestions/policy for how to handle this? I understand that I would
need to test each emacsen provider individually to make sure that it
builds successfully...

Thanks,
-- 
-John Sullivan
-http://wjsullivan.net
-GPG Key: AE8600B6