BUG: Camlimages-2.2 does not build

[erikproper@…]

When doing a ports of camlimages, I get:

File "ps.ml", line 228, characters 14-17:
Warning Y: unused variable dpi.
ocamlc.opt  -I ../corelib -I ../ppm -c oPs.ml
if test "X" = "X"; then \
    ocamlc.opt  -a -linkall -o ci_ps.cma \
           ps.cmo oPs.cmo -ccopt -L/opt/local/lib ; \
  else \
    ocamlmklib -linkall -o ci_ps \
           ps.cmo oPs.cmo -L/opt/local/lib ; \
  fi
ocamlc.opt  -I ../corelib -c graphic_image.mli
File "graphic_image.mli", line 31, characters 33-47:
Unbound type constructor Graphics.color
make[1]: *** [graphic_image.cmi] Error 2
make: *** [byt] Error 2

Warning: the following items did not execute (for camlimages): com.apple.activate com.apple.build com.apple.destroot com.apple.install
Error: Status 1 encountered during processing.