In previous releases, Berkeley DB required separate configuration and builds to create both static and shared libraries. This has changed in the 3.3 release, and Berkeley DB now builds and installs both shared and static versions of the Berkeley DB libraries by default. This change was based on Berkeley DB upgrading to release 1.4 of the GNU Project's Libtool distribution. For this reason, Berkeley DB no longer supports the previous --enable-dynamic and --enable-shared configuration options. Instead, as Berkeley DB now builds both static and shared libraries by default, the useful options are Libtool's --disable-shared and --disable-static options.