DSOs compiled against glibc 2.0 may have referenced to unversioned atexit. But atexit in glibc 2.2.3 is hidden from the static linker. As the result, you can no longer use those DSOs for the final link with glibc 2.2.3. See http://sources.redhat.com/ml/libc-alpha/2001-05/msg00091.html for possible workaround.
Nothing like this has been necessary.