The Thunar SVN Plugin adds Subversion actions to the context menu of thunar.

The current features are:
Most of the svn action: add, blame, checkout, cleanup, commit, copy, delete,
export, import, lock, log, move, properties, relocate, resolved, revert, status,
switch, unlock, update.
Subversion info in file properties dialog.

WWW: http://goodies.xfce.org/projects/thunar-plugins/thunar-svn-plugin