Here is a procedure I use often to establish password-less access to machines:

USERNAME=myusername

HOSTNAME=targetmachine.domain.net

ssh -l $USERNAME $HOSTNAME 'mkdir -p ~/.ssh ; chmod 700 ~/.ssh ; touch ~/.ssh/authorized_keys2; chmod 600 ~/.ssh/authorized_keys2'

cat ~/.ssh/id_dsa.pub | ssh -l $USERNAME $HOSTNAME 'sh -c "cat - >>~/.ssh/authorized_keys2"'

How to find out whether a server supports password-less login:

For positive verification:

ssh -o PasswordAuthentication=no -l $USERNAME $HOSTNAME echo 'access confirmed' 2>&1 | grep 'access confirmed' | wc -l  | awk '{ print $1 }'

For negative verification:

ssh -o PasswordAuthentication=no -l $USERNAME $HOSTNAME echo 'access confirmed' 2>&1 | grep 'Permission denied' | wc -l  | awk '{ print $1 }'