open-database returns nil when type is berkeley-db. However, three files are left open in the process of returning nil. (open-database vm-folders-summary-database 'berkeley-db 'hash "rw+") nil (open-database vm-folders-summary-database nil 'hash "rw+") #<database "/home/jeff/mail/.vm.folders.db" (dbm/nil/readwrite) 0xd245> This is part of the configuration output of building 21.4.6 -jeff checking for ndbm.h... yes checking for dbm_open in -lgdbm... yes checking for Berkeley db.h... db.h checking for Berkeley DB version... 3 checking for db_create... no checking for db_create in -ldb... yes Databases: Compiling in support for Berkeley database. Compiling in support for GNU DBM. Compiling in support for LDAP.