validates_inclusion_of :status, :in => VERSION_STATUSES
validates_inclusion_of :sharing, :in => VERSION_SHARINGS
+ named_scope :named, lambda {|arg| { :conditions => ["LOWER(#{table_name}.name) = LOWER(?)", arg.to_s.strip]}}
named_scope :open, :conditions => {:status => 'open'}
named_scope :visible, lambda {|*args| { :include => :project,
:conditions => Project.allowed_to_condition(args.first || User.current, :view_issues) } }