sftp-server questions

[César Soler]

Hello,

Is there any way to specify which pubkey has rights to use the
sftp-server subsytem when this has been set up in the sshd server?
I don't know if I could control which users are authorized to use the
sftp-server, could I?
Is there any official patch that allows sftp-sessions 'chroot'ed?

Thanks in advance.

-- 
Best regards,
 quart                          mailto:quart at wanadoo.es