SSH: WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!

donghua@rh6:~$ ssh -X root@vmxdb02
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@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
ac:e0:b0:90:72:14:68:fe:3c:4b:a0:f9:64:d6:f4:11.
Please contact your system administrator.
Add correct host key in /home/donghua/.ssh/known_hosts to get rid of this message.
Offending RSA key in /home/donghua/.ssh/known_hosts:1
remove with: ssh-keygen -f "/home/donghua/.ssh/known_hosts" -R vmxdb02
RSA host key for vmxdb02 has changed and you have requested strict checking.
Host key verification failed.
donghua@rh6:~$
donghua@rh6:~$ ssh-keygen -f "/home/donghua/.ssh/known_hosts" -R vmxdb02
/home/donghua/.ssh/known_hosts updated.
Original contents retained as /home/donghua/.ssh/known_hosts.old
donghua@rh6:~$ ssh -X root@vmxdb02
The authenticity of host 'vmxdb02 (192.168.1.22)' can't be established.
RSA key fingerprint is ac:e0:b0:90:72:14:68:fe:3c:4b:a0:f9:64:d6:f4:11.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'vmxdb02' (RSA) to the list of known hosts.
Warning: the RSA host key for 'vmxdb02' differs from the key for the IP address '192.168.1.22'
Offending key for IP in /home/donghua/.ssh/known_hosts:1
Are you sure you want to continue connecting (yes/no)? yes
root@vmxdb02's password:
Last login: Sat May 14 10:10:05 2011
[root@vmxdb02 ~]#