9 files changed, 23 insertions, 12 deletions
diff --git a/Library/Formula/cairo.rb b/Library/Formula/cairo.rb
index 39c2f148a..03ad11326 100644
--- a/Library/Formula/cairo.rb
+++ b/Library/Formula/cairo.rb
@@ -8,8 +8,8 @@ class Cairo < Formula
   depends_on 'pkg-config' => :build
   depends_on 'pixman'
 
-  # Comes with Snow Leopard, but not Leopard
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx,
+            "The Cairo provided by Leopard is too old for newer software to link against."
 
   def install
     system "./configure", "--disable-dependency-tracking",
diff --git a/Library/Formula/curl.rb b/Library/Formula/curl.rb
index f3b95c0f7..18c80b2bb 100644
--- a/Library/Formula/curl.rb
+++ b/Library/Formula/curl.rb
@@ -5,7 +5,8 @@ class Curl < Formula
   homepage 'http://curl.haxx.se/'
   md5 'ca96df88e044c7c25d19692ec8b250b2'
 
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx,
+            "The libcurl provided by Leopard is too old for CouchDB to use."
 
   def install
     system "./configure", "--disable-debug", "--disable-dependency-tracking",
diff --git a/Library/Formula/fontconfig.rb b/Library/Formula/fontconfig.rb
index bf0d85fa5..f4a2b9fce 100644
--- a/Library/Formula/fontconfig.rb
+++ b/Library/Formula/fontconfig.rb
@@ -5,10 +5,10 @@ class Fontconfig < Formula
   homepage 'http://fontconfig.org/'
   md5 '77e15a92006ddc2adbb06f840d591c0e'
 
-  # Leopard comes with 2.4.x, which is too old for many packages.
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx,
+    "Leopard comes with version 2.4.x, which is too old for many packages."
 
-  depends_on 'pkg-config'
+  depends_on 'pkg-config' => :build
 
   def install
     ENV.x11
diff --git a/Library/Formula/libffi.rb b/Library/Formula/libffi.rb
index fec5208fb..3eb9612dc 100644
--- a/Library/Formula/libffi.rb
+++ b/Library/Formula/libffi.rb
@@ -5,7 +5,8 @@ class Libffi < Formula
   homepage 'http://sourceware.org/libffi/'
   sha1 '56e41f87780e09d06d279690e53d4ea2c371ea88'
 
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx,
+            "TODO: What software depends on this newer libffi?"
 
   def install
     ENV.universal_binary
diff --git a/Library/Formula/libiconv.rb b/Library/Formula/libiconv.rb
index 444462071..0eb6043d1 100644
--- a/Library/Formula/libiconv.rb
+++ b/Library/Formula/libiconv.rb
@@ -5,7 +5,10 @@ class Libiconv < Formula
   homepage 'http://www.gnu.org/software/libiconv/'
   md5 '7ab33ebd26687c744a37264a330bbe9a'
 
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx, <<-EOS.undent
+    A few software packages require this newer version of libiconv.
+    Please use this dependency very sparingly.
+  EOS
 
   def patches
     { :p1 => [
diff --git a/Library/Formula/libpng.rb b/Library/Formula/libpng.rb
index ac6dcaf39..a13b0b70a 100644
--- a/Library/Formula/libpng.rb
+++ b/Library/Formula/libpng.rb
@@ -5,7 +5,8 @@ class Libpng < Formula
   homepage 'http://www.libpng.org/pub/png/libpng.html'
   md5 'e3ac7879d62ad166a6f0c7441390d12b'
 
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx,
+            "TODO: Which software depends on this newer version of libpng?"
 
   def install
     system "./configure", "--disable-dependency-tracking", "--prefix=#{prefix}"
diff --git a/Library/Formula/neon.rb b/Library/Formula/neon.rb
index 832bd4c2d..19a147c2d 100644
--- a/Library/Formula/neon.rb
+++ b/Library/Formula/neon.rb
@@ -7,7 +7,8 @@ class Neon < Formula
 
   depends_on 'pkg-config' => :build
 
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx,
+            "Compiling newer versions of Subversion on 10.6 require this newer neon."
 
   def options
     [['--universal', 'Builds a universal binary.']]
diff --git a/Library/Formula/openssl.rb b/Library/Formula/openssl.rb
index a26062da2..90f20b46e 100644
--- a/Library/Formula/openssl.rb
+++ b/Library/Formula/openssl.rb
@@ -6,7 +6,8 @@ class Openssl < Formula
   homepage 'http://www.openssl.org'
   md5 '63ddc5116488985e820075e65fbe6aa4'
 
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx,
+            "OpenSSL provided by Leopard is too old for newer software to link against."
 
   def options
     [["--universal", "Build a universal binary."]]
diff --git a/Library/Formula/texinfo.rb b/Library/Formula/texinfo.rb
index 40f303426..7e49012f5 100644
--- a/Library/Formula/texinfo.rb
+++ b/Library/Formula/texinfo.rb
@@ -5,7 +5,10 @@ class Texinfo < Formula
   homepage 'http://www.gnu.org/software/texinfo/'
   md5 '71ba711519209b5fb583fed2b3d86fcb'
 
-  keg_only :provided_by_osx
+  keg_only :provided_by_osx, <<-EOS.undent
+    Software that uses TeX, such as lilypond and octave, require a newer version
+    of these files.
+  EOS
 
   def install
     system "./configure", "--disable-dependency-tracking",