[exim] queue merging

Slightly obscure question, and I don't see an answer in documentation:
can queues from two exim instances be merged?

Background: I've got a set of machines running exim, with identical
configs, and would like to take some of the older boxes out for
recycling. Simply stopping any new mail from reaching the deprecated
servers means that it'll still take several days for the existing queues
to drain.

Would it be possible to shut down exim, back up the queue (input/* and
msglog/*), take it to one of the other servers, and restore it in
together with whatever mail is already queued on that box? I can
definitely see checking that there aren't any precisely-identical
filenames that would get stomped, and probably want to temporarily shut
down exim on the target host while doing the restore, but I'm wondering
if that exim instance will find the new-to-it mail on startup or if
something has to happen in its db/* databases?

--
Anthony de Boer