WARNING: POSSIBLE DNS SPOOFING DETECTED!

Error :
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@$
@       WARNING: POSSIBLE DNS SPOOFING DETECTED!          @$
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@$
The RSA host key for host1 has changed,$
and the key for the according IP address 10.10.25.5$
is unknown. This could either mean that$
DNS SPOOFING is happening or the IP address for the host$
and its host key have changed at the same time.$
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@$
 @    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 the RSA host key has just been changed.$
 The fingerprint for the RSA key sent by the remote host is$
 g8:ac:7d:8d:df:32:f6:3a:f5:96:31:9a:13:27:eb:38.$
 Please contact your system administrator.$
 Add correct host key in /u/thiagu/.ssh/known_hosts to get rid of this message.$
 Offending key in /u/thiagu/.ssh/known_hosts:5$
 RSA host key for host1 has changed and you have requested strict$
 checking.$
 Host key verification failed.$

Solution:
Entries in known hosts must have outdated. Remove corresponding entry for the machine in /user_home_dir/.ssh/known_hosts  and add a updated one.