I tried to apply attr_readonly :some, :attributes to all none root-nodes of an acts_as_tree model. The important part here is that:
attr_readonly :some, :attributes unless some_condition
doesn't seem to work: all objects have :some and :attributes set to read_only, even if they meet some_condition. After searching for that a little bit, I discovered that it had been corrected in bugmash not that long ago (and now that I mention it, I can only find this ML-post http://osdir.com/ml/RubyonRails:Core/2009-03/msg00022.html ...).
Anyway, does anyone know a way how to get this behaviour on 2.3.3 (other than writing custom setters, of course...)?