diff --git a/extra/kalzium/PKGBUILD b/extra/kalzium/PKGBUILD
index c4a0a0271..42b72bd3f 100644
--- a/extra/kalzium/PKGBUILD
+++ b/extra/kalzium/PKGBUILD
@@ -7,24 +7,30 @@
 
 pkgname=kalzium
 pkgver=17.04.3
-pkgrel=1
+pkgrel=2
 pkgdesc="Periodic Table of Elements"
 url="https://kde.org/applications/education/kalzium/"
 arch=(i686 x86_64)
 license=(GPL LGPL FDL)
 depends=(khtml kdelibs4support knewstuff kplotting openbabel chemical-mime-data)
-makedepends=(extra-cmake-modules kdoctools kdesignerplugin python eigen) # ocaml facile
+makedepends=(extra-cmake-modules kdoctools kdesignerplugin python eigen ocaml facile)
 conflicts=(kdeedu-kalzium)
 replaces=(kdeedu-kalzium)
 groups=(kde-applications kdeedu)
-source=("https://download.kde.org/stable/applications/$pkgver/src/$pkgname-$pkgver.tar.xz"{,.sig})
+source=("https://download.kde.org/stable/applications/$pkgver/src/$pkgname-$pkgver.tar.xz"{,.sig}
+        kalzium-ocaml-4.04.patch)
 sha256sums=('8dfe48d336d746cfc2387d67c5bcb921f9ea4dea1c0231864f7dcd87c35a9d5f'
-            'SKIP')
+            'SKIP'
+            '1bb03588d074331fb78d4647aa038353cc202b9eff20f6bfec95c9e8340dc83b')
 validpgpkeys=(CA262C6C83DE4D2FB28A332A3A6A4DB839EAA6D7  # Albert Astals Cid <aacid@kde.org>
               F23275E4BF10AFC1DF6914A6DBD2CE893E2D1C87) # Christoph Feck <cfeck@kde.org>
 
 prepare() {
   mkdir -p build
+
+# Fix solver build with ocaml 4.04
+  cd $pkgname-$pkgver
+  patch -p2 -i ../kalzium-ocaml-4.04.patch
 }
 
 build() {
diff --git a/extra/kalzium/kalzium-ocaml-4.04.patch b/extra/kalzium/kalzium-ocaml-4.04.patch
new file mode 100644
index 000000000..51a9f7711
--- /dev/null
+++ b/extra/kalzium/kalzium-ocaml-4.04.patch
@@ -0,0 +1,13 @@
+diff --git a/kalzium-17.04.3.orig/src/CMakeOCamlInstructions.cmake b/kalzium-17.04.3/src/CMakeOCamlInstructions.cmake
+--- a/kalzium-17.04.3.orig/src/CMakeOCamlInstructions.cmake
++++ b/kalzium-17.04.3/src/CMakeOCamlInstructions.cmake
+@@ -58,7 +58,7 @@
+ # object files
+ 
+ add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/modwrap.o
+-                   COMMAND ${OCAML_OCAMLOPT_EXECUTABLE} -I ${LIBFACILE_INCLUDE_DIR} -c ${CMAKE_CURRENT_SOURCE_DIR}/solver/modwrap.c -o ${CMAKE_CURRENT_BINARY_DIR}/modwrap.o
++                   COMMAND ${OCAML_OCAMLOPT_EXECUTABLE} -I ${LIBFACILE_INCLUDE_DIR} -c ${CMAKE_CURRENT_SOURCE_DIR}/solver/modwrap.c
+                    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/solver/modwrap.c ${CMAKE_CURRENT_BINARY_DIR}/solver.o
+                    WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+ set_directory_properties(PROPERTIES ADDITIONAL_MAKE_CLEAN_FILES ${CMAKE_CURRENT_BINARY_DIR}/modwrap.o)
+