SSH Access for additonal User

Hi,

I would like to create an additional (restricted) SSH/SFTP user login for my Bitnami Server (Ubuntu), hosted in the EC2 Cloud.

I can perfectly login to the server as the user bitnami. After spending now more than 5 hours, reading a lot of tutorials and trying out everything, I have no more idea what to do.

Following the instructions at the Bitnami Wiki:

http://wiki.bitnami.org/BitNami_Cloud_Hosting/Servers/Access_your_machine#Give_SSH_access_to_the_another_person_or_your_customer

I still receive the error message: Permission denied (publickey) when trying to connect to the server.

I even copied the public keys from /home/user/bitnami/.ssh/authorized_keys into the /home/newuser/.ssh/authorized_keys to make sure that the keys are ok. But even with the identical private/public keys this doesn't work.

What have I overseen?

There is nothing I have to modify in the EC2 settings, right?

Any help is appreciated.

Thanks! Tobias