A bug was opened against bogofilter asking why it still uses db4 instead
of db5:
https://bugzilla.redhat.com/show_bug.cgi?id=1367329
I never changed the BRs because it works and I was never sure how the
upgrade from db4 to db5 would impact the database format of the
bogofilter wordlist.
I just tried to build bogofilter locally against db5 and it still just
works. I can read and write the bogofilter wordlist with both binaries
without a problem. So it seems the on-disk-format of db4 and db5 is the
same or at least compatible. Just wanted to check here if there are any
know problems upgrading from db4 to db5.
Adrian