Class default property of boolean set to true gives false on run-time

I've got a simple component class with boolean property:

  TmyClass = class(TComponent)
    private
      fSomeProperty: boolean;
    published
      property SomeProperty: boolean 
                  read fSomeProperty 
                  write fSomeProperty
                  default true;

  end;

I put it on my form, set it to true (SomeProperty is set to false, why?), but when i'm trying to access SomeProperty from run-time it's giving me false. Why is that so?