[Mediawiki-l] md5sums - mediawiki update

[mac honk]

hi there,
we wanted to update our mediawiki-isntallation with mediawiki 1.12.0.

we noticed the patch file and the tar.gz have wrong md5 sums here:
http://lists.wikimedia.org/pipermail/mediawiki-announce/2008-October/000078.html

is there any "normal" reason for this ? we would like to get our  
mediawiki up-to-date,
thankful for any help!
greetings,
elias
ps:
is it wiser / less hassle to backup everything (config, db, skins) and  
then reinstall with 1.13.2 ??