I have been playing a bit with anonymous subclasses, and instances of anon subclasses seem slower to execute code than "regular" subclasses instances, but sometimes they reach equivalent performances (for code defined in anon-subclasses). I don't understand why. I have a class A with a method m. B is subclass of A with a new method m1. Anon-A is an anonymous class of A which also implements the m1 method. I did various tests of speed and: - when executing m, compiled in A, instances of Anon-A are around 10% slower than instances of B - when executing m1, compiled in B and in Anon-A, performances are equivalent between instances of B and of anon-A Is that a particular behavior of anonymous subclasses, like their instances can easily find behavior defined in their class but have to perform extra-work to find methods defined in their superclass (which is not anonymous) ? Is that vm related ? Other ? Steven.