diff --git a/pkgs/tools/graphics/ploticus/default.nix b/pkgs/tools/graphics/ploticus/default.nix
index e5d9f7160789..6b1b50bca02b 100644
--- a/pkgs/tools/graphics/ploticus/default.nix
+++ b/pkgs/tools/graphics/ploticus/default.nix
@@ -6,13 +6,13 @@
 , libpng
 }:
 
-stdenv.mkDerivation {
+stdenv.mkDerivation rec {
   pname = "ploticus";
   version = "2.42";
 
   src = fetchurl {
-    url = "mirror://sourceforge/ploticus/ploticus/2.41/pl241src.tar.gz";
-    sha256 = "1065r0nizjixi9sxxfxrnwg10r458i6fgsd23nrxa200rypvdk7c";
+    url = "mirror://sourceforge/ploticus/ploticus/${version}/ploticus${lib.replaceStrings [ "." ] [ "" ] version}_src.tar.gz";
+    sha256 = "PynkufQFIDqT7+yQDlgW2eG0OBghiB4kHAjKt91m4LA=";
   };
 
   patches = [
@@ -46,11 +46,7 @@ stdenv.mkDerivation {
     mkdir -p "$out/share/ploticus/prefabs"
     cp -rv prefabs/* "$out/share/ploticus/prefabs"
 
-    # Install the man pages.
-    cp -rv man $out/share
-
     # Add aliases for backwards compatibility.
-    ln -s "pl.1" "$out/share/man/man1/ploticus.1"
     ln -s "pl" "$out/bin/ploticus"
   '';
 
diff --git a/pkgs/tools/graphics/ploticus/set-prefabs-dir.patch b/pkgs/tools/graphics/ploticus/set-prefabs-dir.patch
index 3955d34972e5..82871654fdea 100644
--- a/pkgs/tools/graphics/ploticus/set-prefabs-dir.patch
+++ b/pkgs/tools/graphics/ploticus/set-prefabs-dir.patch
@@ -1,10 +1,11 @@
---- a/src/Makefile
-+++ b/src/Makefile
-@@ -133,6 +133,6 @@
- #### To set a hard-coded directory for prefabs files, uncomment & edit the following..
- #### If done, users won't be required to have PLOTICUS_PREFABS environment variable defined.
- #### This option not available for win32
--# PREFABS_DIR = "/usr/lib/ploticus/prefabs"
-+PREFABS_DIR = "$(out)/share/ploticus/prefabs"
+--- a/src/pl.h
++++ b/src/pl.h
+@@ -8,7 +8,7 @@
+ #include <stdlib.h>
+ #include "plg.h"
  
+-#define PREFABS_DIR ""  	 /* INSTALLERS can set this to a valid pathname, so that users don't need to set PLOTICUS_PREFABS env var */
++#define PREFABS_DIR "@out@/share/ploticus/prefabs"  	 /* INSTALLERS can set this to a valid pathname, so that users don't need to set PLOTICUS_PREFABS env var */
+ 
+ #define PLVERSION "2.42-May2013" /* see also the Copyright page, and page headers and footers */