[Fab-user] reject_unknown_hosts option

[Antônio Theóphilo]

Hi everybody

I'm using SSH agent/public key to authenticate hosts and everything works well 
until I enable env.reject_unknown_hosts. When this happens, Fabric asks for a 
password (what shouldn't because we are using ssh-agent) and even when the 
correct password is entered, we receive "Fatal error: Unknown server 10.0.1.2" 
message (obviously 10.0.1.2 is on ~/.ssh/known_hosts). Is Fabric looking for a 
different known_hosts file? Below are my versions and the env dict output:

OpenBSD 4.9
bash-4.1.9p0        GNU Bourne Again Shell
py-crypto-2.0.1p7   cryptographic tools for Python
py-paramiko-1.7.6p0 Python module that implements the SSH2 protocol
py-setuptools-0.6.11p1v0 simplified packaging system for Python modules
python-2.6.6p0      interpreted object-oriented programming language
Fabric 1.2.2 (via easy_install)

[10.0.1.2] Executing task 'test'
{'abort_on_prompts': False,
 'again_prompt': 'Sorry, try again.',
 'all_hosts': ['10.0.1.2'],
 'always_use_pty': True,
 'combine_stderr': True,
 'command': 'test',
 'command_prefixes': [],
 'cwd': '',
 'disable_known_hosts': False,
 'echo_stdin': True,
 'exclude_hosts': [],
 'fabfile': 'fabfile',
 'gateway': None,
 'hide': None,
 'host': '10.0.1.2',
 'host_string': '10.0.1.2',
 'hosts': ['10.0.1.2'],
 'keepalive': 0,
 'key_filename': None,
 'lcwd': '',
 'local_user': 'fabric',
 'new_style_tasks': True,
 'no_agent': False,
 'no_keys': False,
 'output_prefix': True,
 'password': None,
 'passwords': {},
 'path': '',
 'path_behavior': 'append',
 'port': '22',
 'rcfile': '/home/fabric/.fabricrc',
 'real_fabfile': '/home/fabric/fabric/fabfile.py',
 'reject_unknown_hosts': True,
 'roledefs': {},
 'roles': [],
 'shell': '/usr/local/bin/bash -l -c',
 'show': None,
 'sudo_prefix': "sudo -S -p '%s' ",
 'sudo_prompt': 'sudo password:',
 'use_shell': True,
 'user': 'fabric',
 'version': '1.2.2',
 'warn_only': False}
[10.0.1.2] run: hostname
[10.0.1.2] Login password: 

Fatal error: Unknown server 10.0.1.2

Aborting.

Regards
Antonio