(let ((p-len (length pickle))
        (acc (new-account)))
    (cffi:with-foreign-string ((foreign-key foreign-key-length) passphrase)
      (cffi:with-foreign-pointer-as-string (p-buffer p-len)
        (unwind-protect 
             (save-pointers acc (foreign-key p-buffer)
               (setf (account acc)
                     (%olm:unpickle-account (account acc) foreign-key
                                            foreign-key-length p-buffer p-len)))
          (loop :for i :from 0 :below foreign-key-length
                :do (setf (cffi:mem-aref foreign-key :uint8 i) 0))))
      (check-error acc)
      acc)))