It's already on garage, right, and GeneralAntilles (and maybe others) has been commiting stuff as far as I can see. lcuk, if you did your development in the svn-checkedout version it should be just to first merge the svn changes back to the local copy: svn update
Then, after resolving any conflicts, to push local changes back up: svn commit
(But it's really much easier to do this continually, updating and commiting change by change.. )

If the local changes were done outside an svn tree then unpacking the tree over an svn checkout could be problematic, as it could easily overwrite/miss out changes done to the svn repository. In that case it would be better to create a branch and commit the changes there, later to be merged back to the trunk.