diff --git a/pkgs/applications/science/logic/iprover/default.nix b/pkgs/applications/science/logic/iprover/default.nix
index af225a2961d5..d3950349711b 100644
--- a/pkgs/applications/science/logic/iprover/default.nix
+++ b/pkgs/applications/science/logic/iprover/default.nix
@@ -2,11 +2,11 @@
 
 stdenv.mkDerivation rec {
   name = "iprover-${version}";
-  version = "2.5";
+  version = "2018_Jul_24_11h";
 
   src = fetchurl {
-    url = "http://www.cs.man.ac.uk/~korovink/iprover/iprover-v${version}.tar.gz";
-    sha256 = "1mbxjczp6nqw0p33glqmw973c268yzy4gxflk1lfiyiihrjdhinb";
+    url = "http://www.cs.man.ac.uk/~korovink/iprover/iprover_${version}.tar.gz";
+    sha256 = "1iqim11flzm56aaysasl5whajcv1gq31hkidaqfr8ww7kwl1h06p";
   };
 
   buildInputs = [ ocaml eprover zlib ];
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index e3f6f5f32253..98101ec847cd 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -21499,9 +21499,7 @@ with pkgs;
     java = if stdenv.isLinux then jre else jdk;
   };
 
-  iprover = callPackage ../applications/science/logic/iprover {
-    inherit (ocaml-ng.ocamlPackages_4_02) ocaml;
-  };
+  iprover = callPackage ../applications/science/logic/iprover { };
 
   jonprl = callPackage ../applications/science/logic/jonprl {
     smlnj = if stdenv.isDarwin