uebayasi@soum.co.jp said:
> It's good that Emacs 20.x and 21.x can be installed simultaneously, on
> the other hand, interface change (new command names, e.g. bin/emacs21)
> may confuse users, and package maintainance cost may become bigger. 

Imho, there is not that much need to have Emacs 20 and 21
simultanously to justify the confusion and maintainance work.
There might be initial build problems on some platforms,
that's why it is probably a good idea to keep the old package
around, but this is an either-or thing.
(unless there are Emacs add-ons which require Emacs 20...)

Thanks for your work to get the pkg work with USE_BUILDLINK_ONLY!
I've started to integrate the changes, but I'll not get it done
this week.
(will be AKF until Thursday next week)

best regards
Matthias