[SOLVED] Problem with GIT update - Possible DNS spoofing detected [SOLVED]

When I tried to update my local GIT repo, I got the warning below.
I don't know if this is serious (i.e. attack) or not. I found a pastebin entry from someone else with the same message, so I'm not the only one.

What am I supposed to do? Reconfigure something, ignore it?

sev@####:~/xonotic> ./all update
Repository . enabled because it already exists
Repository data/xonotic-data.pk3dir enabled because it already exists
Repository data/xonotic-music.pk3dir enabled because it already exists
Repository data/xonotic-nexcompat.pk3dir disabled by default, create data/xonotic-nexcompat.pk3dir.yes to enable
Repository darkplaces enabled because it already exists
Repository netradiant enabled because it already exists
Repository div0-gittools disabled by default, create div0-gittools.yes to enable
Repository data/xonotic-maps.pk3dir enabled because it already exists
Repository mediasource disabled by default, create mediasource.yes to enable
Repository fteqcc enabled because it already exists
+ cd /home/sev/xonotic/.
+ git config core.autocrlf input
+ git config remote.origin.url ssh://xonotic@git.xonotic.org/xonotic.git
+ git config remote.origin.fetch +refs/heads/*:refs/remotes/origin/*
+ git pull
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
The RSA host key for git.xonotic.org has changed,
and the key for the corresponding IP address 87.250.139.171
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
07:b7:44:20:b5:60:f8:97:c8:f3:da:d3:08:0d:93:45.
Please contact your system administrator.
Add correct host key in /home/sev/.ssh/known_hosts to get rid of this message.
Offending key in /home/sev/.ssh/known_hosts:1
RSA host key for git.xonotic.org has changed and you have requested strict checking.
Host key verification failed.
fatal: The remote end hung up unexpectedly
Pulling failed. Press ENTER to continue, or Ctrl-C to abort.

The fingerprint (07:b7:44:20:b5:60:f8:97:c8:f3:da:d3:08:0d:93:45) is correct, you can fix this by opening a shell (if you're on windows, a msys shell) and typing

Code:

ssh-keygen -R git.xonotic.org

Code:

ssh-keygen -R git.xonotic.org

Seems to work fine again, thanks for your quick reply.