[gentoo-user] Copying files from one encfs directory to another encfs directory

Hi,

I have two separaly mounted directories, both mounted/encrypted
via encfs.

When I try to copy files (cp or via two tars piped together) from
one directory to the other I get "permission denied" -- with
both directories I am owner and read/write permissions.

How can I copy a large quantity of files between the directories
without using temprary storage somewhere else?

Best regards,
mcc