Redmine

Using bitnami redmine stack:
Redmine 1.2.1.stable.3
MySQL 5.0.83
Ruby 1.8.7
Rubygems 1.6.2
Rails 2.3.11
SVN 1.6.15
I can't get script/about to work :(

I have set up redmine to look at a pre-existing repository on a different server. That all works fine, but I would like to have it ignore whitespace changes when diffing.
I found #1476 and changed the line in subversion_adapter.rb (although it had changed slightly since then, it looked like it did the same thing) and restarted Redmine, but now receive 404 errors whenever I try to diff.
Changing it back fixed the 404 problem, and so that is how it is for now, but it would be nice to have it ignore whitespace.