Can't compile the current version

Hello,
I'm trying to use Goji, but when I do make, I get the following errors

```
OCAMLPATH=. ocamlfind ocamlopt -g -package dynlink,str,unix,pprint,cmdliner,goji_lib,findlib -c goji_pprint.ml
File "goji_pprint.ml", line 9, characters 21-27:
Error: Unbound value column
```

I don't know if it comes from pprint, I'm using the latest version from Opam.
