> +                 ;; Groovy uses class loading. It's not enough to put the class
> +                 ;; in the loader's classpath, as it causes breakages:
> +                 ;; the compiler would give this error:
> +                 ;; "Prohibited package name: java.lang"

It might make sense to ask upstream about that.

> +                 ;; antlr.jar is present twice in antlr2.  Symlink doesn't like
> +                 ;; it, so we symlink it here.

Why is it present twice?  Is it useful?

So this package uses an union in order to avoid classloader problems.  Fine, but I wonder whether the problem is now merely hidden.

Anyway, LGTM for now (for this version) !