1.7 Thu Jul 17 14:09:25 CEST 2008
    - use a totally different mechanism to pass callbacks to requests (see
        manpage).
    - optional arguments before the callback can now be left out.
    - use less memory per request, probably be a bit faster, too.
    - fix a memory leak (callbacks were never freed).
    - add a basic testsuite.
    - add (untested) support for cdsgroup_begin and db_exists.
    - make BDB::VERSION compatible to UNIVERSAL::VERSION.
    1.6 Tue Jul 8 10:34:58 CEST 2008
    - add new BDB::VERSION function for easy version checks.
    - work around broken bsd headers once more.
    - support for berkeley db 4.7 added.
    - add support for log_set_config and it's constants, and
        set_intermediate_dir_mode.
    - add db_env_dbrename and db_env_dbremove.