To understand how the VR plugin works check this forum.
In AS you have the config.columns[:name].description mechanism to add descriptors to fields. Binding VR with AS you’ll have:

1
2

 
config.columns[:name].description = get_validation_option(Department, "name", :validates_length_of, :within, nil)

Related posts

• Steps to learn building a Rails application — compiled after one year of learning
• [Howto] Add refresh button to ActiveScaffold
• [Howto] Let users add/remove list columns in ActiveScaffold
• [Howto] Render show / custom action on a controller handled by ActiveScaffold
• [Howto] ActiveScaffold configuration using parameters
• [Howto] Select excluded columns in ActiveScaffold associated forms
• [Howto] ActiveScaffold with RedBox modal windows for ‘edit associated’
• [Howto] Remove nested records instead of delete in Activescaffold
• [Howto] Integrate FCKeditor into ActiveScaffold
• [Howto] Integrate TinyMCE into ActiveScaffold
• BetterNestedSet Better?
• [Howto] BetterNestedSet and ActiveScaffold
• Rich Text Editor for Rails
• [Howto] Database column name conventions
• [Howto] ActiveScaffold
• Hobo