Dear Maintainer, I tried to find out what happens and I think it is related to the changes from #928467. Because of these the configure script searches now for libdb-5.3.a in directory /usr/lib/i686-linux-gnu (in configure "$dir/lib/${host_cpu}-${host_os}").
Unfortunately that library lives in /usr/lib/i386-linux-gnu. Changing in debian/rules the --host and --build arguments to DEB_..._MULTIARCH would make the package build in i386, but I cannot say if that would defeat the whole purpose of the change in #928467, therefore I hope its ok CCing to Helmut Grohne. Kind regards, Bernhard