Command explanations --enable-compat185: Build support for older database files. --prefix=/opt/db-3.1.17: This version of the Berkeley Database should not be installed in /usr, as it is only needed for the building of Evolution. --with-db3=/opt/db-3.1.17: Specify the location where db-3.1.17 is installed. --enable-openssl: This flag will compile SSL support into Evolution. --with-openldap: This flag will compile LDAP support into Evolution.