I am not sure if this is related to this very similar looking issue.
I am running drush in a GIT Bash shell on Windows/XP and when I use the drush ckeditor-download command I get this error message:

Drush was unable to download CKEditor to g:/wamp/www/d7build/sites/all/libraries/ckeditor.
Attempted command: svn checkout http://svn.ckeditor.com/releases/stable

I presume that SVN is not installed because the svn command does not work in GIT Bash (command not found)