ocamlnet-4.1.7 doesn't compile with OCaml 4.0.0

# opam install ocamlnet
The following actions will be performed:
  - install ocamlnet 4.1.7

<><> Gathering sources ><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ocamlnet.4.1.7] found in cache

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ERROR] The compilation of ocamlnet failed at
        "/home/berenger/.opam/opam-init/hooks/sandbox.sh build make all".

#=== ERROR while compiling ocamlnet.4.1.7 =====================================#
# context     2.0.3 | linux/x86_64 | ocaml-base-compiler.4.00.0 | git+https://github.com/ocaml/opam-repository.git
# path        ~/.opam/4.00.0/.opam-switch/build/ocamlnet.4.1.7
# command     ~/.opam/opam-init/hooks/sandbox.sh build make all
# exit-code   2
# env-file    ~/.opam/log/ocamlnet-19074-c61e7b.env
# output-file ~/.opam/log/ocamlnet-19074-c61e7b.out
### output ###
# [...]
# ../../tools/stubcc -ocamlc ocamlc -ccopt "-O -g"   netsys_c.c
# + gcc -fno-defer-pop -Wall -D_FILE_OFFSET_BITS=64 -D_REENTRANT -fPIC -c  -O -g  -I'/home/berenger/.opam/4.00.0/lib/ocaml' 'netsys_c.c'
# In file included from netsys_c.c:5:0:
# netsys_c.h:69:10: fatal error: caml/version.h: No such file or directory
#  #include "caml/version.h"
#           ^~~~~~~~~~~~~~~~
# compilation terminated.
# ../../Makefile.rules:143: recipe for target 'netsys_c.o' failed
# make[1]: *** [netsys_c.o] Error 2
# make[1]: Leaving directory '/home/berenger/.opam/4.00.0/.opam-switch/build/ocamlnet.4.1.7/src/netsys'
# Makefile:23: recipe for target 'all' failed
# make: *** [all] Error 2



<><> Error report <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
+- The following actions failed
| - build ocamlnet 4.1.7
+- 
- No changes have been performed