I think this might be a Mac OS X only bug. Mac OS X stores filenames
case sensitively but compares filenames without case sensitivity.
same file:
script/…/config/…/public/document/thumbnail/tmp/1137259310.479525.806/barcelona.JPG
and
script/…/config/…/public/document/thumbnail/tmp/1137259310.479525.806/barcelona.jpg
/usr/lib/ruby/1.8/fileutils.rb:846:in fu_each_src_dest' /usr/lib/ruby/1.8/fileutils.rb:845:infu_each_src_dest0’
/usr/lib/ruby/1.8/fileutils.rb:845:in fu_each_src_dest' /usr/lib/ruby/1.8/fileutils.rb:572:inmv’
./script/…/config/…/vendor/plugins/file_column/lib/file_column.rb:247:in
`store_upload’