diff --git a/pkgs/development/libraries/openssl-0.9.8/default.nix b/pkgs/development/libraries/openssl-0.9.8/default.nix
index f39b4fb8f63..da0b88e98c2 100644
--- a/pkgs/development/libraries/openssl-0.9.8/default.nix
+++ b/pkgs/development/libraries/openssl-0.9.8/default.nix
@@ -9,5 +9,5 @@
 
   # Quick fix for a Makefile bug in openssl-0.9.8 (`make install'
   # tries to copy .so files, instead of .dylib files).
-  patches = if stdenv.system == "powerpc-darwin" then [./dylib.patch] else [];
+  patches = if stdenv.isDarwin then [./dylib.patch] else [];
 }
diff --git a/pkgs/development/libraries/openssl/openssl-0.9.8b.nix b/pkgs/development/libraries/openssl/openssl-0.9.8b.nix
index 873a8ec8722..15e3c8a0475 100644
--- a/pkgs/development/libraries/openssl/openssl-0.9.8b.nix
+++ b/pkgs/development/libraries/openssl/openssl-0.9.8b.nix
@@ -6,5 +6,4 @@
     sha1 = "99565db630a044fa484d4f91006a31908f262246";
   };
   buildInputs = [perl];
-#  patches = [./darwin-makefile.patch];
 }
diff --git a/pkgs/tools/compression/bzip2/default.nix b/pkgs/tools/compression/bzip2/default.nix
index c54b619fc4c..be387bb46be 100644
--- a/pkgs/tools/compression/bzip2/default.nix
+++ b/pkgs/tools/compression/bzip2/default.nix
@@ -3,7 +3,7 @@
 stdenv.mkDerivation {
   name = "bzip2-1.0.3";
   builder =
-    if stdenv.system == "powerpc-darwin" || stdenv.system == "i686-darwin" then ./builder-darwin.sh
+    if stdenv.isDarwin then ./builder-darwin.sh
     else if stdenv.system == "i686-freebsd" then ./builder-freebsd.sh
     else if stdenv.system == "i686-cygwin" then ./builder-cygwin.sh
     else ./builder.sh;
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index b6b70daf7a1..1c5f5396bfe 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -58,9 +58,6 @@ rec {
       );
     };
 
-  # Check if stdenv.system denotes Mac OS X.
-  isDarwin = stdenv: stdenv.system == "powerpc-darwin" || stdenv.system == "i686-darwin";
-
 
   ### STANDARD ENVIRONMENT
 
@@ -737,7 +734,7 @@ rec {
   };
 
   jdk = 
-    if isDarwin stdenv then 
+    if stdenv.isDarwin then 
       "/System/Library/Frameworks/JavaVM.framework/Versions/1.5.0/Home"
     else
       (import ../development/compilers/jdk) {
@@ -937,7 +934,7 @@ rec {
   php = (import ../development/interpreters/php) {
     inherit stdenv fetchurl flex bison libxml2 apacheHttpd;
     unixODBC =
-      if isDarwin stdenv then null else unixODBC;
+      if stdenv.isDarwin then null else unixODBC;
   };
 
   guile = (import ../development/interpreters/guile) {