Support for legacy passwords hashed by Apostrophe 1.5 / Symfony 1.4 / sfDoctrineGuardPlugin. These are hashed and salted but the salt is applied differently so the regular password-hash module doesn't like them. It is simple, though, to check them directly with the crypto module. To leverage this support set the "algorithm" part of the password string to "a15sha1" (you may suffix a different algorithm if your algorithm column in sf_guard_user is not sha1, just prefix it with a15). apostropheA2ExportPlugin supports this.