According to GCC 4.0 as the default GCC / C++ ABI change, I rebuild qdbm, which provides C++ library libqdbm2++ that doesn't depend on any other C++ libraries besides libstdc++. I rename libqdbm2++ to libqdbm2++c2 and make libqdbm2++c2 conflicts/replaces libqdbm2++. I've got several warnings(?) from dh_strip -a:

dh_strip -a
BFD: debian/libqdbm++-dev/usr/lib/sto1kaxx/xadbm.o: no group info for section .gnu.linkonce.d._ZTIN4qdbm9DBM_errorE
BFD: debian/libqdbm++-dev/usr/lib/sto1kaxx/xadbm.o: no group info for section .gnu.linkonce.r._ZTSN4qdbm9DBM_errorE
BFD: debian/libqdbm++-dev/usr/lib/sto1kaxx/xadbm.o: no group info for section .gnu.linkonce.d._ZTIN4qdbm5DatumE
BFD: debian/libqdbm++-dev/usr/lib/sto1kaxx/xadbm.o: no group info for section .gnu.linkonce.r._ZTSN4qdbm5DatumE
BFD: debian/libqdbm++-dev/usr/lib/sto1kaxx/xadbm.o: no group info for section .gnu.linkonce.d._ZTVN4qdbm9DBM_errorE
(snip)

What's this?

I also got other warning from dh_shlibdeps -a:

dh_shlibdeps -a -l debian/libqdbm11/usr/lib:debian/libqdbm2++c2/usr/lib
Use of uninitialized value in scalar assignment at /usr/bin/dh_shlibdeps line 138, <COMPAT_IN> line 1.
Use of uninitialized value in scalar assignment at /usr/bin/dh_shlibdeps line 138, <COMPAT_IN> line 1.
(snip)

Hmm, it may be $ENV{LD_LIBRARY_PATH} was not defined, so $ld_library_path_orig would be uninitialized.