Redmine

Hi. I'm new to ruby and redmine and I'm currently evaluating redmine as a replacement for mantis.
One of my problem is the fact that the description is not included in the history list.
So far, I have done the following modification in the app/models/issue.rb (line 428)
old: (Issue.column_names - %w(id description lock_version created_on updated_on)).each {|c|
new: (Issue.column_names - %w(id lock_version created_on updated_on)).each {|c|
(Using Redmine 0.9.3.stable.3591 )
In order to have the modification in the description field tracked.
It does seem to work, However I must ask, why was this excluded in the first place?